2008
|
Guden, Mustafa; Celik, Emrah; Hizal, Alpay; Altindis, Mustafa; Cetiner, Sinan Effects of compaction pressure and particle shape on the porosity and
compression mechanical properties of sintered Ti6Al4V powder compacts
for hard tissue implantation Journal Article JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS, 85B (2), pp. 547-555, 2008, ISSN: 1552-4973. Abstract | Links | BibTeX @article{ISI:000255180900029,
title = {Effects of compaction pressure and particle shape on the porosity and
compression mechanical properties of sintered Ti6Al4V powder compacts
for hard tissue implantation},
author = {Mustafa Guden and Emrah Celik and Alpay Hizal and Mustafa Altindis and Sinan Cetiner},
doi = {10.1002/jbm.b.30978},
issn = {1552-4973},
year = {2008},
date = {2008-05-01},
journal = {JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS},
volume = {85B},
number = {2},
pages = {547-555},
abstract = {Sintered Ti6Al4V powder compacts potentially to be used in implant
applications were prepared using commercially available spherical and
angular powders (100-200 mu m) within the porosity range of 34-54%.
Cylindrical green powder compacts were cold compacted at various
pressures and then sintered at 1200 degrees C for 2 h. The final percent
porosity and mean pore sizes were determined as functions of the applied
compaction pressure and powder type. The mechanical properties were
investigated through compression testing. Results have shown that yield
strength of the powder compacts of 40-42% porosity was comparable with
that of human cortical bone. As compared with previously investigated Ti
powder compacts, Ti6Al4V powder compacts showed higher strength at
similar porosity range. Microscopic observations on the failed compact
samples revealed that failure occurred primarily by the separation of
interparticle bond regions in the planes 45 degrees to the loading axis.
(C) 2007 Wiley Periodicals, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Sintered Ti6Al4V powder compacts potentially to be used in implant
applications were prepared using commercially available spherical and
angular powders (100-200 mu m) within the porosity range of 34-54%.
Cylindrical green powder compacts were cold compacted at various
pressures and then sintered at 1200 degrees C for 2 h. The final percent
porosity and mean pore sizes were determined as functions of the applied
compaction pressure and powder type. The mechanical properties were
investigated through compression testing. Results have shown that yield
strength of the powder compacts of 40-42% porosity was comparable with
that of human cortical bone. As compared with previously investigated Ti
powder compacts, Ti6Al4V powder compacts showed higher strength at
similar porosity range. Microscopic observations on the failed compact
samples revealed that failure occurred primarily by the separation of
interparticle bond regions in the planes 45 degrees to the loading axis.
(C) 2007 Wiley Periodicals, Inc. |
Ince, Umut; Toksoy, Macit; Guden, Mustafa Testing corrosion rates on steel piping in geothermal district heating Journal Article MATERIALS PERFORMANCE, 47 (5), pp. 56-59, 2008, ISSN: 0094-1492. Abstract | BibTeX @article{ISI:000255758800018,
title = {Testing corrosion rates on steel piping in geothermal district heating},
author = {Umut Ince and Macit Toksoy and Mustafa Guden},
issn = {0094-1492},
year = {2008},
date = {2008-05-01},
journal = {MATERIALS PERFORMANCE},
volume = {47},
number = {5},
pages = {56-59},
abstract = {The St-37 carbon steel piping in a geothermal heating system experienced
increasing corrosion leaks. Tests with pipe steel coupons showed that
while uniform corrosion rates were low, pitting rates were high.
Sulfate-reducing bacteria were the main cause. Changes in fluid
velocities and the addition of a bacteriacide were recommended.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The St-37 carbon steel piping in a geothermal heating system experienced
increasing corrosion leaks. Tests with pipe steel coupons showed that
while uniform corrosion rates were low, pitting rates were high.
Sulfate-reducing bacteria were the main cause. Changes in fluid
velocities and the addition of a bacteriacide were recommended. |
Aktay, L; Kroeplin, B -H; Toksoy, A K; Guden, M Finite element and coupled finite element/smooth particle hydrodynamics
modeling of the quasi-static crushing of empty and foam-filled single,
bitubular and constraint hexagonal- and square-packed aluminum tubes Journal Article MATERIALS & DESIGN, 29 (5), pp. 952-962, 2008, ISSN: 0261-3069. Abstract | Links | BibTeX @article{ISI:000255088000006,
title = {Finite element and coupled finite element/smooth particle hydrodynamics
modeling of the quasi-static crushing of empty and foam-filled single,
bitubular and constraint hexagonal- and square-packed aluminum tubes},
author = {L Aktay and B -H Kroeplin and A K Toksoy and M Guden},
doi = {10.1016/j.matdes.2007.03.019},
issn = {0261-3069},
year = {2008},
date = {2008-01-01},
journal = {MATERIALS & DESIGN},
volume = {29},
number = {5},
pages = {952-962},
abstract = {The quasi-static axial crushing behavior of empty and Al and polystyrene
foam-filled Al single, bitubular and multi-tube-packed (hexagonal and
square packing) configurations were investigated experimentally and
numerically. Tubes were modeled using finite element and coupled finite
element/smooth particle hydrodynamics. The numerical specific absorbed
energy (SAE) values, deformation patterns, load values and number of
folds formed were found to show agreements with those of experiments.
Among the tested tube configurations only hexagonal- and square-packed
empty tube designs showed increased SAE values over that of single empty
tube. Furthermore, foam-filled multi-tube designs both hexagonal- and
square-packed designs were found energetically more efficient than Al
foam-filled single tubes at similar foam filler densities. The increased
SAE values of multi-tubes were attributed to the frictional forces of
the multi-tube designs and constraining effect of the die walls
accommodating the tubes. (c) 2007 Elsevier Ltd. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The quasi-static axial crushing behavior of empty and Al and polystyrene
foam-filled Al single, bitubular and multi-tube-packed (hexagonal and
square packing) configurations were investigated experimentally and
numerically. Tubes were modeled using finite element and coupled finite
element/smooth particle hydrodynamics. The numerical specific absorbed
energy (SAE) values, deformation patterns, load values and number of
folds formed were found to show agreements with those of experiments.
Among the tested tube configurations only hexagonal- and square-packed
empty tube designs showed increased SAE values over that of single empty
tube. Furthermore, foam-filled multi-tube designs both hexagonal- and
square-packed designs were found energetically more efficient than Al
foam-filled single tubes at similar foam filler densities. The increased
SAE values of multi-tubes were attributed to the frictional forces of
the multi-tube designs and constraining effect of the die walls
accommodating the tubes. (c) 2007 Elsevier Ltd. All rights reserved. |
Aktay, L; Johnson, A F; Toksoy, A K; Kroeplin, B -H; Guden, M Modeling the progressive axial crushing of foam-filled aluminum tubes
using smooth particle hydrodynamics and coupled finite element
model/smooth particle hydrodynamics Journal Article MATERIALS & DESIGN, 29 (3), pp. 569-575, 2008, ISSN: 0261-3069. Abstract | Links | BibTeX @article{ISI:000253189800001,
title = {Modeling the progressive axial crushing of foam-filled aluminum tubes
using smooth particle hydrodynamics and coupled finite element
model/smooth particle hydrodynamics},
author = {L Aktay and A F Johnson and A K Toksoy and B -H Kroeplin and M Guden},
doi = {10.1016/j.matdes.2007.03.010},
issn = {0261-3069},
year = {2008},
date = {2008-01-01},
journal = {MATERIALS & DESIGN},
volume = {29},
number = {3},
pages = {569-575},
abstract = {As alternatives to the classical finite element model (FEM), a meshless
smooth particle hydrodynamics (SPH) method, in which the discrete
particles represent a solid domain, and a coupled FEM/SPH modeling
technique were investigated for the numerical simulation of the
quasi-static axial crushing of polystyrene foam-filled aluminum
thin-walled aluminum tubes. The results of numerical simulations,
load-deformation histories, fold lengths and specific absorbed energies,
were found to show satisfactory correlations with those of experiments
and FEM. The results further proved the capabilities of the SPH Method
and coupled FEM/SPH modeling technique in predicting the crushing
behavior of foam-filled thin-walled tubes. (C) 2007 Elsevier Ltd. All
rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
As alternatives to the classical finite element model (FEM), a meshless
smooth particle hydrodynamics (SPH) method, in which the discrete
particles represent a solid domain, and a coupled FEM/SPH modeling
technique were investigated for the numerical simulation of the
quasi-static axial crushing of polystyrene foam-filled aluminum
thin-walled aluminum tubes. The results of numerical simulations,
load-deformation histories, fold lengths and specific absorbed energies,
were found to show satisfactory correlations with those of experiments
and FEM. The results further proved the capabilities of the SPH Method
and coupled FEM/SPH modeling technique in predicting the crushing
behavior of foam-filled thin-walled tubes. (C) 2007 Elsevier Ltd. All
rights reserved. |
2007
|
Guden, M; Yueksel, S; Tasdemirci, A; Tanoglu, M Effect of aluminum closed-cell foam filling on the quasi-static axial
crush performance of glass fiber reinforced polyester composite and
aluminum/composite hybrid tubes Journal Article COMPOSITE STRUCTURES, 81 (4), pp. 480-490, 2007, ISSN: 0263-8223. Abstract | Links | BibTeX @article{ISI:000249256200002,
title = {Effect of aluminum closed-cell foam filling on the quasi-static axial
crush performance of glass fiber reinforced polyester composite and
aluminum/composite hybrid tubes},
author = {M Guden and S Yueksel and A Tasdemirci and M Tanoglu},
doi = {10.1016/j.compstruct.2006.09.005},
issn = {0263-8223},
year = {2007},
date = {2007-12-01},
journal = {COMPOSITE STRUCTURES},
volume = {81},
number = {4},
pages = {480-490},
abstract = {The effect of Al closed-cell foam filling on the quasi-static crushing
behavior of an E-glass woven fabric polyester composite tube and
thin-walled Al/polyester composite hybrid tube was experimentally
investigated. For comparison, empty Al, empty composite and empty hybrid
tubes were also tested. Empty composite and empty hybrid tubes crushed
predominantly in progressive crushing mode, without applying any
triggering mechanism. Foam filling was found to be ineffective in
increasing the crushing loads of the composite tubes over the sum of the
crushing loads of empty composite tube and foam. However, foam filling
stabilized the composite progressive crushing mode. In empty hybrid
tubes, the deformation mode of the inner Al tube was found to be a more
complex form of the diamond mode of deformation of empty Al tube,
leading to higher crushing load values than the sum of the crushing load
values of empty composite tube and empty metal tube. The foam filling of
hybrid tubes however resulted in axial splitting of the outer composite
tube due to the resistance imposed by the foam filler to Al tube inward
folding and hence it was ineffective in increasing crushing load and SAE
values over those of empty hybrid tubes. (C) 2006 Elsevier Ltd. All
rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The effect of Al closed-cell foam filling on the quasi-static crushing
behavior of an E-glass woven fabric polyester composite tube and
thin-walled Al/polyester composite hybrid tube was experimentally
investigated. For comparison, empty Al, empty composite and empty hybrid
tubes were also tested. Empty composite and empty hybrid tubes crushed
predominantly in progressive crushing mode, without applying any
triggering mechanism. Foam filling was found to be ineffective in
increasing the crushing loads of the composite tubes over the sum of the
crushing loads of empty composite tube and foam. However, foam filling
stabilized the composite progressive crushing mode. In empty hybrid
tubes, the deformation mode of the inner Al tube was found to be a more
complex form of the diamond mode of deformation of empty Al tube,
leading to higher crushing load values than the sum of the crushing load
values of empty composite tube and empty metal tube. The foam filling of
hybrid tubes however resulted in axial splitting of the outer composite
tube due to the resistance imposed by the foam filler to Al tube inward
folding and hence it was ineffective in increasing crushing load and SAE
values over those of empty hybrid tubes. (C) 2006 Elsevier Ltd. All
rights reserved. |
2006
|
Guden, M; Toksoy, A K; Kavi, H Experimental investigation of interaction effects in foam-filled
thin-walled aluminum tubes Journal Article JOURNAL OF MATERIALS SCIENCE, 41 (19), pp. 6417-6424, 2006, ISSN: 0022-2461. Abstract | Links | BibTeX @article{ISI:000241379600030,
title = {Experimental investigation of interaction effects in foam-filled
thin-walled aluminum tubes},
author = {M Guden and A K Toksoy and H Kavi},
doi = {10.1007/s10853-006-0722-3},
issn = {0022-2461},
year = {2006},
date = {2006-10-01},
journal = {JOURNAL OF MATERIALS SCIENCE},
volume = {41},
number = {19},
pages = {6417-6424},
abstract = {The interaction coefficients of polystyrene foam filling of thin-walled
aluminum cylindrical tubes were investigated experimentally through
compression testing of partially foam-filled tubes with and without
adhesive. The experimental load-displacement curves and observation of
the crushed sections of filled tubes have shown that partial foam
filling reduced the fold length and hence increased the average crushing
loads of tubes, proving the interaction effect between tube wall and
filler. The interaction coefficients for the partial foam filling were
further calculated to be in the level and/or higher than that of the
foam plateau load of transverse direction.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The interaction coefficients of polystyrene foam filling of thin-walled
aluminum cylindrical tubes were investigated experimentally through
compression testing of partially foam-filled tubes with and without
adhesive. The experimental load-displacement curves and observation of
the crushed sections of filled tubes have shown that partial foam
filling reduced the fold length and hence increased the average crushing
loads of tubes, proving the interaction effect between tube wall and
filler. The interaction coefficients for the partial foam filling were
further calculated to be in the level and/or higher than that of the
foam plateau load of transverse direction. |
Aidarova, S B; Musabekov, K B; Ospanova, Z B; Guden, M Foaming binary solution mixtures of low molecular surfactant and
polyelectrolyte Journal Article JOURNAL OF MATERIALS SCIENCE, 41 (13), pp. 3979-3986, 2006, ISSN: 0022-2461, (Conference on Syntactic and Composite Foams, Banff, CANADA, AUG 01-05,
2004). Abstract | Links | BibTeX @article{ISI:000239282300004,
title = {Foaming binary solution mixtures of low molecular surfactant and
polyelectrolyte},
author = {S B Aidarova and K B Musabekov and Z B Ospanova and M Guden},
doi = {10.1007/s10853-006-7573-9},
issn = {0022-2461},
year = {2006},
date = {2006-07-01},
journal = {JOURNAL OF MATERIALS SCIENCE},
volume = {41},
number = {13},
pages = {3979-3986},
organization = {ECI},
abstract = {The lifetime of water solution foams of sodium dodecylsulfate (DDS, low
molecular weight surfactant) and sodium carboxymethylcellulose (SCMC,
polyelectrolyte) and their binary mixtures was experimentally
investigated. The effects of ionic strength and acidity on the foam life
were also determined. In binary solutions, a synergic effect of DDS and
SCMC on the surface tension reduction, most likely resulting from the
interaction of the surfactant with polymer, was found. The addition of
NaCl into solution or increasing the ionic strength was found to
decrease the surface tension and reduce interfacial mobility, hence
increased foam lifetime. The relatively low lifetime of binary solution
foams in acidic medium was attributed to the reaction between SCMC and
acid, which resulted in relatively small reductions in the viscosity and
consequently lowered the solution viscosity. (c) 2006 Springer Science +
Business Media, Inc.},
note = {Conference on Syntactic and Composite Foams, Banff, CANADA, AUG 01-05,
2004},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The lifetime of water solution foams of sodium dodecylsulfate (DDS, low
molecular weight surfactant) and sodium carboxymethylcellulose (SCMC,
polyelectrolyte) and their binary mixtures was experimentally
investigated. The effects of ionic strength and acidity on the foam life
were also determined. In binary solutions, a synergic effect of DDS and
SCMC on the surface tension reduction, most likely resulting from the
interaction of the surfactant with polymer, was found. The addition of
NaCl into solution or increasing the ionic strength was found to
decrease the surface tension and reduce interfacial mobility, hence
increased foam lifetime. The relatively low lifetime of binary solution
foams in acidic medium was attributed to the reaction between SCMC and
acid, which resulted in relatively small reductions in the viscosity and
consequently lowered the solution viscosity. (c) 2006 Springer Science +
Business Media, Inc. |
Guden, M; Yuksel, S SiC-particulate aluminum composite foams produced from powder compacts:
foaming and compression behavior Journal Article JOURNAL OF MATERIALS SCIENCE, 41 (13), pp. 4075-4084, 2006, ISSN: 0022-2461, (Conference on Syntactic and Composite Foams, Banff, CANADA, AUG 01-05,
2004). Abstract | Links | BibTeX @article{ISI:000239282300014,
title = {SiC-particulate aluminum composite foams produced from powder compacts:
foaming and compression behavior},
author = {M Guden and S Yuksel},
doi = {10.1007/s10853-006-7645-x},
issn = {0022-2461},
year = {2006},
date = {2006-07-01},
journal = {JOURNAL OF MATERIALS SCIENCE},
volume = {41},
number = {13},
pages = {4075-4084},
organization = {ECI},
abstract = {The foaming behavior of SiC-particulate (SiCp) aluminum composite powder
compacts containing titanium hydricle blowing agent was investigated by
heating to 750 degrees C in a pre-heated furnace. Aluminum powder
compacts were also prepared and foamed using similar compaction and
foaming parameters in order to determine the effect of SiCp-addition on
the foaming and compression behavior. The SiCp-addition (10 wt%) was
found to increase the linear expansion of the Al powder compacts
presumably by increasing the surface as well as the bulk viscosities.
The compression tests conducted on Al and 10 and 20% SiCp foams further
showed a more brittle compression behavior of SiCp/Al foams as compared
with Al foams. The collapse stresses of Al and 10% SiCp/Al foams were
also predicted using the equations developed for the open and closed
cell foams. Predictions have shown that Al foam samples behaved similar
to open cell foams, while 10% SiCp/Al foam collapse stress values were
found between those of open and closed cell foams, biasing towards those
of the open cell foams. (c) 2006 Springer Science + Business Media, Inc.},
note = {Conference on Syntactic and Composite Foams, Banff, CANADA, AUG 01-05,
2004},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The foaming behavior of SiC-particulate (SiCp) aluminum composite powder
compacts containing titanium hydricle blowing agent was investigated by
heating to 750 degrees C in a pre-heated furnace. Aluminum powder
compacts were also prepared and foamed using similar compaction and
foaming parameters in order to determine the effect of SiCp-addition on
the foaming and compression behavior. The SiCp-addition (10 wt%) was
found to increase the linear expansion of the Al powder compacts
presumably by increasing the surface as well as the bulk viscosities.
The compression tests conducted on Al and 10 and 20% SiCp foams further
showed a more brittle compression behavior of SiCp/Al foams as compared
with Al foams. The collapse stresses of Al and 10% SiCp/Al foams were
also predicted using the equations developed for the open and closed
cell foams. Predictions have shown that Al foam samples behaved similar
to open cell foams, while 10% SiCp/Al foam collapse stress values were
found between those of open and closed cell foams, biasing towards those
of the open cell foams. (c) 2006 Springer Science + Business Media, Inc. |
Guden, M; Akil, O; Tasdemirci, A; Ciftcioglu, M; Hall, I W Effect of strain rate on the compressive mechanical behavior of a
continuous alumina fiber reinforced ZE41A magnesium alloy based
composite Journal Article MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES
MICROSTRUCTURE AND PROCESSING, 425 (1-2), pp. 145-155, 2006, ISSN: 0921-5093. Abstract | Links | BibTeX @article{ISI:000241151500019,
title = {Effect of strain rate on the compressive mechanical behavior of a
continuous alumina fiber reinforced ZE41A magnesium alloy based
composite},
author = {M Guden and O Akil and A Tasdemirci and M Ciftcioglu and I W Hall},
doi = {10.1016/j.msea.2006.03.028},
issn = {0921-5093},
year = {2006},
date = {2006-06-01},
journal = {MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES
MICROSTRUCTURE AND PROCESSING},
volume = {425},
number = {1-2},
pages = {145-155},
abstract = {The compressive mechanical response of an FP (TM) continuous fiber (35
vol.%) Mg composite has been determined in the transverse and
longitudinal directions at quasi-static and high strain rates. It was
found that the composite in the transverse direction exhibited strain
rate sensitivity of the flow stress and maximum stress within the
studied strain-rate range of 1.3 x 10(-4) to 1550 s(-1). The failure
strain in this direction, however, decreased with increasing strain
rate. Microscopic observations on the failed samples have shown that the
composite failed by shear banding along the diagonal axis, 45 degrees to
the loading axis. Twinning was observed in the deformed cross-sections
of the samples particularly in and near the shear band region. The
strain rate sensitivity of the fracture stress of the composite in
transverse direction is attributed to the matrix strain rate
sensitivity. In the longitudinal direction, the composite failed by kink
formation at quasi-static strain rates, while kinking and splitting were
observed at the high strain rates. The maximum stress in the
longitudinal direction was, however, found to be strain rate insensitive
within the strain rate regime of 1.3 x 10(-4) to 500 s(-1). In this
direction, similar to transverse direction, twinning was observed in the
highly deformed kink region. Several different reasons are proposed for
the strain rate insensitive compressive strength in this direction. (c)
2006 Elsevier B.V. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The compressive mechanical response of an FP (TM) continuous fiber (35
vol.%) Mg composite has been determined in the transverse and
longitudinal directions at quasi-static and high strain rates. It was
found that the composite in the transverse direction exhibited strain
rate sensitivity of the flow stress and maximum stress within the
studied strain-rate range of 1.3 x 10(-4) to 1550 s(-1). The failure
strain in this direction, however, decreased with increasing strain
rate. Microscopic observations on the failed samples have shown that the
composite failed by shear banding along the diagonal axis, 45 degrees to
the loading axis. Twinning was observed in the deformed cross-sections
of the samples particularly in and near the shear band region. The
strain rate sensitivity of the fracture stress of the composite in
transverse direction is attributed to the matrix strain rate
sensitivity. In the longitudinal direction, the composite failed by kink
formation at quasi-static strain rates, while kinking and splitting were
observed at the high strain rates. The maximum stress in the
longitudinal direction was, however, found to be strain rate insensitive
within the strain rate regime of 1.3 x 10(-4) to 500 s(-1). In this
direction, similar to transverse direction, twinning was observed in the
highly deformed kink region. Several different reasons are proposed for
the strain rate insensitive compressive strength in this direction. (c)
2006 Elsevier B.V. All rights reserved. |
Sakar-Deliormanli, A; Guden, M Microhardness and fracture toughness of dental materials by indentation
method Journal Article JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS, 76B (2), pp. 257-264, 2006, ISSN: 1552-4973. Abstract | Links | BibTeX @article{ISI:000234834700003,
title = {Microhardness and fracture toughness of dental materials by indentation
method},
author = {A Sakar-Deliormanli and M Guden},
doi = {10.1002/jbm.b.30371},
issn = {1552-4973},
year = {2006},
date = {2006-02-01},
journal = {JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART B-APPLIED BIOMATERIALS},
volume = {76B},
number = {2},
pages = {257-264},
abstract = {The main objective of this study was to measure the fracture toughness
of the human teeth enamel using the microindentation technique and to
compare the results calculated from the equations developed for
Palmqvist and radial-median cracks. Vickers microhardness measurements
of dental ceramic (alumina) and human teeth were performed using
indentation fracture method. The fracture toughness of enamel was
calculated using different equations reported in the literature. Vickers
microhardness or the sintered alumina specimen (98.8% theoretical
density) was measured to be 14.92 GPa under 9.8N indentation load. Three
equations based oil the radial-median cracks were found to be applicable
for the fracture toughness determination or the enamel. Results show
that indentation fracture method is adequate to measure microhardness
and fracture toughness of dental materials. However the calculation of
fracture toughness depended oil the nature of the cracks and also oil
the location of the indentation. Therefore, it is necessary to identify
the crack profile and to select the appropriate equation for accurate
fracture toughness values. (c) 2005 Wiley Periodicals, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The main objective of this study was to measure the fracture toughness
of the human teeth enamel using the microindentation technique and to
compare the results calculated from the equations developed for
Palmqvist and radial-median cracks. Vickers microhardness measurements
of dental ceramic (alumina) and human teeth were performed using
indentation fracture method. The fracture toughness of enamel was
calculated using different equations reported in the literature. Vickers
microhardness or the sintered alumina specimen (98.8% theoretical
density) was measured to be 14.92 GPa under 9.8N indentation load. Three
equations based oil the radial-median cracks were found to be applicable
for the fracture toughness determination or the enamel. Results show
that indentation fracture method is adequate to measure microhardness
and fracture toughness of dental materials. However the calculation of
fracture toughness depended oil the nature of the cracks and also oil
the location of the indentation. Therefore, it is necessary to identify
the crack profile and to select the appropriate equation for accurate
fracture toughness values. (c) 2005 Wiley Periodicals, Inc. |
Kavi, H; Toksoy, AK; Guden, M Predicting energy absorption in a foam-filled thin-walled aluminum tube
based on experimentally determined strengthening coefficient Journal Article MATERIALS & DESIGN, 27 (4), pp. 263-269, 2006, ISSN: 0264-1275. Abstract | Links | BibTeX @article{ISI:000233836800001,
title = {Predicting energy absorption in a foam-filled thin-walled aluminum tube
based on experimentally determined strengthening coefficient},
author = {H Kavi and AK Toksoy and M Guden},
doi = {10.1016/j.matdes.2004.10.024},
issn = {0264-1275},
year = {2006},
date = {2006-01-01},
journal = {MATERIALS & DESIGN},
volume = {27},
number = {4},
pages = {263-269},
abstract = {The energy absorption in a foam-filled thin-walled circular AI tube was
investigated based on the experimentally determined strengthening
coefficient of filling using AI and polystyrene closed-cell foams with
three different densities. Foam filling was found to change the
deformation mode of tube from diamond (empty tube) into concertina,
regardless the foam type and density used. Although foam filling
resulted in higher energy absorption than the sum of the energy
absorptions of the tube alone and foam alone, it was not effective in
increasing the specific energy than simply thickening the tube wall. It
was shown that for efficient foam filling an appropriate foam-tube
combination Must be selected by taking into account the magnitude of
strengthening coefficient of foam filling and the foam filler plateau
load. (c) 2004 Elsevier Ltd. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The energy absorption in a foam-filled thin-walled circular AI tube was
investigated based on the experimentally determined strengthening
coefficient of filling using AI and polystyrene closed-cell foams with
three different densities. Foam filling was found to change the
deformation mode of tube from diamond (empty tube) into concertina,
regardless the foam type and density used. Although foam filling
resulted in higher energy absorption than the sum of the energy
absorptions of the tube alone and foam alone, it was not effective in
increasing the specific energy than simply thickening the tube wall. It
was shown that for efficient foam filling an appropriate foam-tube
combination Must be selected by taking into account the magnitude of
strengthening coefficient of foam filling and the foam filler plateau
load. (c) 2004 Elsevier Ltd. All rights reserved. |
Aktay, L; Toksoy, AK; Guden, M Quasi-static axial crushing of extruded polystyrene foam-filled
thin-walled aluminum tubes: Experimental and numerical analysis Journal Article MATERIALS & DESIGN, 27 (7), pp. 556-565, 2006, ISSN: 0264-1275. Abstract | Links | BibTeX @article{ISI:000236222500003,
title = {Quasi-static axial crushing of extruded polystyrene foam-filled
thin-walled aluminum tubes: Experimental and numerical analysis},
author = {L Aktay and AK Toksoy and M Guden},
doi = {10.1016/j.matdes.2004.12.019},
issn = {0264-1275},
year = {2006},
date = {2006-01-01},
journal = {MATERIALS & DESIGN},
volume = {27},
number = {7},
pages = {556-565},
abstract = {The experimental and numerical quasi-static crushing responses of
extruded closed cell polystyrene foam-filled thin-walled aluminum tubes
were investigated. The numerical crash analysis of empty and foam-filled
tubes was performed using the explicit finite element code
PAM-CRASH(TM). Satisfactory agreements were generally achieved between
the finite element model and experimental deformed shapes,
load-displacements, fold lengths and specific energy absorptions. The
model and experiments have also highlighted the several effects of foam
filling on the crushing of thin-walled tubes. The energy absorptions in
foam-filled tubes were further shown to be higher than the sum of the
energy absorptions of empty tube (alone) and filler (alone). (C) 2005
Elsevier Ltd. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The experimental and numerical quasi-static crushing responses of
extruded closed cell polystyrene foam-filled thin-walled aluminum tubes
were investigated. The numerical crash analysis of empty and foam-filled
tubes was performed using the explicit finite element code
PAM-CRASH(TM). Satisfactory agreements were generally achieved between
the finite element model and experimental deformed shapes,
load-displacements, fold lengths and specific energy absorptions. The
model and experiments have also highlighted the several effects of foam
filling on the crushing of thin-walled tubes. The energy absorptions in
foam-filled tubes were further shown to be higher than the sum of the
energy absorptions of empty tube (alone) and filler (alone). (C) 2005
Elsevier Ltd. All rights reserved. |
2005
|
Guden, M; Celik, E; Akar, E; Cetiner, S Compression testing of a sintered Ti6Al4V powder compact for biomedical
applications Journal Article MATERIALS CHARACTERIZATION, 54 (4-5), pp. 399-408, 2005, ISSN: 1044-5803. Abstract | Links | BibTeX @article{ISI:000229270700014,
title = {Compression testing of a sintered Ti6Al4V powder compact for biomedical
applications},
author = {M Guden and E Celik and E Akar and S Cetiner},
doi = {10.1016/j.matchar.2005.01.006},
issn = {1044-5803},
year = {2005},
date = {2005-05-01},
journal = {MATERIALS CHARACTERIZATION},
volume = {54},
number = {4-5},
pages = {399-408},
abstract = {in this study, the compression deformation behavior of a Ti6A14V powder
compact, prepared by the sintering of cold compacted atomized spherical
particles (100-200 mu m) and containing 36-38% porosity, was
investigated at quasi-static (1.6 x 10(-3)-1.6 x 10(-1) s(-1)) and high
strain rates (300 and 900 s-1) using, respectively, conventional
mechanical testing and Split Hopkinson Pressure Bar techniques.
Microscopic studies of as-received powder and sintered powder compact
showed that sintering at high temperature (1200 degrees C) and
subsequent slow rate of cooling in the furnace changed the
microstructure of powder from the acicular alpha (alpha) to the
Widmanstdtten (alpha+beta) microstructure. In compression testing, at
both quasi-static and high strain rates, the compact failed via shear
bands formed along the diagonal axis, 45 degrees to the loading
direction. Increasing the strain rate was found to increase both the
flow stress and compressive strength of the compact but it did not
affect the critical strain for shear localization. Microscopic analyses
of failed samples and deformed but not failed samples of the compact
further showed that fracture occurred in a ductile (dimpled) mode
consisting of void initiation and growth in alpha phase and/or at the
alpha/beta interface and macrocracking by void coalescence in the
interparticle bond region. (c) 2005 Elsevier Inc. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
in this study, the compression deformation behavior of a Ti6A14V powder
compact, prepared by the sintering of cold compacted atomized spherical
particles (100-200 mu m) and containing 36-38% porosity, was
investigated at quasi-static (1.6 x 10(-3)-1.6 x 10(-1) s(-1)) and high
strain rates (300 and 900 s-1) using, respectively, conventional
mechanical testing and Split Hopkinson Pressure Bar techniques.
Microscopic studies of as-received powder and sintered powder compact
showed that sintering at high temperature (1200 degrees C) and
subsequent slow rate of cooling in the furnace changed the
microstructure of powder from the acicular alpha (alpha) to the
Widmanstdtten (alpha+beta) microstructure. In compression testing, at
both quasi-static and high strain rates, the compact failed via shear
bands formed along the diagonal axis, 45 degrees to the loading
direction. Increasing the strain rate was found to increase both the
flow stress and compressive strength of the compact but it did not
affect the critical strain for shear localization. Microscopic analyses
of failed samples and deformed but not failed samples of the compact
further showed that fracture occurred in a ductile (dimpled) mode
consisting of void initiation and growth in alpha phase and/or at the
alpha/beta interface and macrocracking by void coalescence in the
interparticle bond region. (c) 2005 Elsevier Inc. All rights reserved. |
Toksoy, AK; Guden, M The strengthening effect of polystyrene foam filling in aluminum
thin-walled cylindrical tubes Journal Article THIN-WALLED STRUCTURES, 43 (2), pp. 333-350, 2005, ISSN: 0263-8231. Abstract | Links | BibTeX @article{ISI:000226331700008,
title = {The strengthening effect of polystyrene foam filling in aluminum
thin-walled cylindrical tubes},
author = {AK Toksoy and M Guden},
doi = {10.1016/j.tws.2004.07.007},
issn = {0263-8231},
year = {2005},
date = {2005-02-01},
journal = {THIN-WALLED STRUCTURES},
volume = {43},
number = {2},
pages = {333-350},
abstract = {The strengthening effect of foam filling in thin-walled circular tubes,
deforming in diamond and concertina modes, was investigated in
polystyrene foam filled aluminum tubes. Empty tubes of two different
diameters (16 and 25 mm) deformed in diamond mode, while foam filling
changed the deformation mode into concertina in 25 mm tube due to
thickening effect of foam filling. The strengthening coefficient in
concertina mode was found around unity, while in diamond mode it was
greater than unity. In concertina mode, foam and tube were observed to
deform independently. However, in diamond mode, foam was compressed in
between the folds, leading to a higher strengthening coefficient. The
effects of deformation rate and the use adhesive on the average crushing
loads of the filled tubes were also determined. (C) 2004 Elsevier Ltd.
All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The strengthening effect of foam filling in thin-walled circular tubes,
deforming in diamond and concertina modes, was investigated in
polystyrene foam filled aluminum tubes. Empty tubes of two different
diameters (16 and 25 mm) deformed in diamond mode, while foam filling
changed the deformation mode into concertina in 25 mm tube due to
thickening effect of foam filling. The strengthening coefficient in
concertina mode was found around unity, while in diamond mode it was
greater than unity. In concertina mode, foam and tube were observed to
deform independently. However, in diamond mode, foam was compressed in
between the folds, leading to a higher strengthening coefficient. The
effects of deformation rate and the use adhesive on the average crushing
loads of the filled tubes were also determined. (C) 2004 Elsevier Ltd.
All rights reserved. |
2004
|
Guden, M; Yildirim, U; Hall, IW Effect of strain rate on the compression behavior of a woven glass
fiber/SC-15 composite Journal Article POLYMER TESTING, 23 (6), pp. 719-725, 2004, ISSN: 0142-9418. Abstract | Links | BibTeX @article{ISI:000223093900014,
title = {Effect of strain rate on the compression behavior of a woven glass
fiber/SC-15 composite},
author = {M Guden and U Yildirim and IW Hall},
doi = {10.1016/j.polymertesting.2004.01.004},
issn = {0142-9418},
year = {2004},
date = {2004-09-01},
journal = {POLYMER TESTING},
volume = {23},
number = {6},
pages = {719-725},
abstract = {Strain rate dependent compression behavior of a plain-weave S-2 glass
fabric SC-15 epoxy (rubber toughened resin) composite plate, currently
studied as the backing plate for composite armor applications, was
determined in the through-thickness direction (normal to the fiber
plane) in the strain rate regime of 1 x 10(-4) to 1.1 x 103 s(-1). In
the studied strain rate regime, the modulus and failure strength of the
composite were found to be rate sensitive and increased with increasing
strain rate. Microscopic observations showed that the composite failed
by ductile failure, involving matrix cracks and, later, cracking through
and between the fiber layers. Crack deflections at rubber
particle/matrix interface and particle pull-out were observed in the
failed samples, contributing to the toughness of the composite. (C) 2004
Elsevier Ltd. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Strain rate dependent compression behavior of a plain-weave S-2 glass
fabric SC-15 epoxy (rubber toughened resin) composite plate, currently
studied as the backing plate for composite armor applications, was
determined in the through-thickness direction (normal to the fiber
plane) in the strain rate regime of 1 x 10(-4) to 1.1 x 103 s(-1). In
the studied strain rate regime, the modulus and failure strength of the
composite were found to be rate sensitive and increased with increasing
strain rate. Microscopic observations showed that the composite failed
by ductile failure, involving matrix cracks and, later, cracking through
and between the fiber layers. Crack deflections at rubber
particle/matrix interface and particle pull-out were observed in the
failed samples, contributing to the toughness of the composite. (C) 2004
Elsevier Ltd. All rights reserved. |
2003
|
Akil, O; Yildirim, U; Guden, M; Hall, IW Effect of strain rate on the compression behaviour of a woven fabric
S2-glass fiber reinforced vinyl ester composite Journal Article POLYMER TESTING, 22 (8), pp. 883-887, 2003, ISSN: 0142-9418. Abstract | Links | BibTeX @article{ISI:000186300400006,
title = {Effect of strain rate on the compression behaviour of a woven fabric
S2-glass fiber reinforced vinyl ester composite},
author = {O Akil and U Yildirim and M Guden and IW Hall},
doi = {10.1016/S0142-9418(03)00026-6},
issn = {0142-9418},
year = {2003},
date = {2003-12-01},
journal = {POLYMER TESTING},
volume = {22},
number = {8},
pages = {883-887},
abstract = {Quasi-static (similar to10(-3)s(-1)) and high strain rate ( > 500 s(-1))
compression behavior of ail S2-glass woven fabric/vinyl ester composite
plate was determined in the in-plane and through-thickness directions.
In both directions, modulus and failure strength increased with
increasing strain rate. A higher strain rate sensitive modulus was found
in the through-thickness direction while a higher strain rate sensitive
failure strength was found in the in-plane direction. In the inplane
direction, the failure mode was observed to change from splitting
followed by ``kink banding'' (localized fiber buckling) to
predominantly splitting at increasing strain rates, while it remained
the same in the through-thickness direction. (C) 2003 Elsevier Ltd. All
rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Quasi-static (similar to10(-3)s(-1)) and high strain rate ( > 500 s(-1))
compression behavior of ail S2-glass woven fabric/vinyl ester composite
plate was determined in the in-plane and through-thickness directions.
In both directions, modulus and failure strength increased with
increasing strain rate. A higher strain rate sensitive modulus was found
in the through-thickness direction while a higher strain rate sensitive
failure strength was found in the in-plane direction. In the inplane
direction, the failure mode was observed to change from splitting
followed by ``kink banding'' (localized fiber buckling) to
predominantly splitting at increasing strain rates, while it remained
the same in the through-thickness direction. (C) 2003 Elsevier Ltd. All
rights reserved. |
Elbir, S; Yilmaz, S; Toksoy, AK; Guden, M SiC-particulate aluminum composite foams produced by powder compacts:
Foaming and compression behavior Journal Article JOURNAL OF MATERIALS SCIENCE, 38 (23), pp. 4745-4755, 2003, ISSN: 0022-2461. Abstract | Links | BibTeX @article{ISI:000186420800012,
title = {SiC-particulate aluminum composite foams produced by powder compacts:
Foaming and compression behavior},
author = {S Elbir and S Yilmaz and AK Toksoy and M Guden},
doi = {10.1023/A:1027427102837},
issn = {0022-2461},
year = {2003},
date = {2003-12-01},
journal = {JOURNAL OF MATERIALS SCIENCE},
volume = {38},
number = {23},
pages = {4745-4755},
abstract = {The foaming behavior of SiC-particulate (8.6% by volume) aluminum
composite powder compacts contained Titanium Hydride blowing agent was
investigated by heating above the melting temperature (750degreesC) in a
pre-heated furnace. Aluminum powder compacts were also prepared and
foamed using similar compaction and foaming parameters in order to
determine the effect of SiC-particulate addition on foaming and
compression behavior. The linear expansions of the compacts at various
furnace holding times were ex situ determined. Optical and scanning
electron microscopy techniques were used to characterize prepared and
deformed foams microstructures. The SiC-particulate addition was found
to increase the linear expansion and reduce the extent of the liquid
metal drainage and cell coarsening of the aluminum compacts. The
composite foam samples also showed higher compressive stresses, but a
more brittle behavior as compared with aluminum foams. (C) 2003 Kluwer
Academic Publishers.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The foaming behavior of SiC-particulate (8.6% by volume) aluminum
composite powder compacts contained Titanium Hydride blowing agent was
investigated by heating above the melting temperature (750degreesC) in a
pre-heated furnace. Aluminum powder compacts were also prepared and
foamed using similar compaction and foaming parameters in order to
determine the effect of SiC-particulate addition on foaming and
compression behavior. The linear expansions of the compacts at various
furnace holding times were ex situ determined. Optical and scanning
electron microscopy techniques were used to characterize prepared and
deformed foams microstructures. The SiC-particulate addition was found
to increase the linear expansion and reduce the extent of the liquid
metal drainage and cell coarsening of the aluminum compacts. The
composite foam samples also showed higher compressive stresses, but a
more brittle behavior as compared with aluminum foams. (C) 2003 Kluwer
Academic Publishers. |
Hall, IW; Guden, M Split Hopkinson Pressure Bar compression testing of an aluminum alloy:
Effect of lubricant type Journal Article JOURNAL OF MATERIALS SCIENCE LETTERS, 22 (21), pp. 1533-1535, 2003, ISSN: 0261-8028. Links | BibTeX @article{ISI:000185963100017,
title = {Split Hopkinson Pressure Bar compression testing of an aluminum alloy:
Effect of lubricant type},
author = {IW Hall and M Guden},
doi = {10.1023/A:1026167517837},
issn = {0261-8028},
year = {2003},
date = {2003-11-01},
journal = {JOURNAL OF MATERIALS SCIENCE LETTERS},
volume = {22},
number = {21},
pages = {1533-1535},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Lopatnikov, SL; Gama, BA; Haque, MJ; Krauthauser, C; Gillespie, JW; Guden, M; Hall, IW Dynamics of metal foam deformation during Taylor cylinder-Hopkinson bar
impact experiment Journal Article COMPOSITE STRUCTURES, 61 (1-2), pp. 61-71, 2003, ISSN: 0263-8223, (14th US National Congress of Theoretical and Applied Mechanics,
BLACKSBURG, VIRGINIA, JUN 23-28, 2002). Abstract | Links | BibTeX @article{ISI:000183147900007,
title = {Dynamics of metal foam deformation during Taylor cylinder-Hopkinson bar
impact experiment},
author = {SL Lopatnikov and BA Gama and MJ Haque and C Krauthauser and JW Gillespie and M Guden and IW Hall},
doi = {10.1016/S0263-8223(03)00039-4},
issn = {0263-8223},
year = {2003},
date = {2003-07-01},
journal = {COMPOSITE STRUCTURES},
volume = {61},
number = {1-2},
pages = {61-71},
abstract = {Analytical solutions for dynamic deformation of foam materials during
the Taylor cylinder-Hopkinson bar impact experiment were obtained. It
was shown that shock wave of foam collapse appears during the fast
impact. The results of this experiment can be used in estimating the
average material properties of the foam under dynamic loading
conditions. Results show that the undeformed and change in length of
foam specimens are in good agreement between theory and experiment, as
well as numerical analysis. (C) 2003 Published by Elsevier Science Ltd.},
note = {14th US National Congress of Theoretical and Applied Mechanics,
BLACKSBURG, VIRGINIA, JUN 23-28, 2002},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Analytical solutions for dynamic deformation of foam materials during
the Taylor cylinder-Hopkinson bar impact experiment were obtained. It
was shown that shock wave of foam collapse appears during the fast
impact. The results of this experiment can be used in estimating the
average material properties of the foam under dynamic loading
conditions. Results show that the undeformed and change in length of
foam specimens are in good agreement between theory and experiment, as
well as numerical analysis. (C) 2003 Published by Elsevier Science Ltd. |
2002
|
Greene, SA; Hall, IW; Guden, M Improving the energy absorption of closed cell aluminum foams Journal Article JOURNAL OF MATERIALS SCIENCE LETTERS, 21 (20), pp. 1591-1593, 2002, ISSN: 0261-8028. Links | BibTeX @article{ISI:000178181700011,
title = {Improving the energy absorption of closed cell aluminum foams},
author = {SA Greene and IW Hall and M Guden},
doi = {10.1023/A:1020361331280},
issn = {0261-8028},
year = {2002},
date = {2002-10-01},
journal = {JOURNAL OF MATERIALS SCIENCE LETTERS},
volume = {21},
number = {20},
pages = {1591-1593},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Hall, IW; Guden, M; Claar, TD Transverse and longitudinal crushing of aluminum-foam filled tubes Journal Article SCRIPTA MATERIALIA, 46 (7), pp. 513-518, 2002, ISSN: 1359-6462. Abstract | Links | BibTeX @article{ISI:000175844200006,
title = {Transverse and longitudinal crushing of aluminum-foam filled tubes},
author = {IW Hall and M Guden and TD Claar},
doi = {10.1016/S1359-6462(02)00024-6},
issn = {1359-6462},
year = {2002},
date = {2002-04-01},
journal = {SCRIPTA MATERIALIA},
volume = {46},
number = {7},
pages = {513-518},
abstract = {Al-foam filled and empty tubes of aluminum, brass and titanium were
compression tested laterally. The specific energy absorption in filled
tubes increased greatly in terms of percentages, and was greatest in
aluminum tubes. In transversely tested tubes the foam deformed laterally
showing a capability of spreading the deformation. (C) 2002 Acta
Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Al-foam filled and empty tubes of aluminum, brass and titanium were
compression tested laterally. The specific energy absorption in filled
tubes increased greatly in terms of percentages, and was greatest in
aluminum tubes. In transversely tested tubes the foam deformed laterally
showing a capability of spreading the deformation. (C) 2002 Acta
Materialia Inc. Published by Elsevier Science Ltd. All rights reserved. |
2001
|
Hall, IW; Guden, M High strain rate testing of a unidirectionally reinforced graphite epoxy
composite Journal Article JOURNAL OF MATERIALS SCIENCE LETTERS, 20 (10), pp. 897-899, 2001, ISSN: 0261-8028. Links | BibTeX @article{ISI:000169504000005,
title = {High strain rate testing of a unidirectionally reinforced graphite epoxy
composite},
author = {IW Hall and M Guden},
doi = {10.1023/A:1010968514339},
issn = {0261-8028},
year = {2001},
date = {2001-05-01},
journal = {JOURNAL OF MATERIALS SCIENCE LETTERS},
volume = {20},
number = {10},
pages = {897-899},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Hall, IW; Ebil, O; Guden, M; Yu, CJ Quasi-static and dynamic crushing of empty and foam-filled tubes Journal Article JOURNAL OF MATERIALS SCIENCE, 36 (24), pp. 5853-5860, 2001, ISSN: 0022-2461. Abstract | Links | BibTeX @article{ISI:000172368200017,
title = {Quasi-static and dynamic crushing of empty and foam-filled tubes},
author = {IW Hall and O Ebil and M Guden and CJ Yu},
doi = {10.1023/A:1012916408297},
issn = {0022-2461},
year = {2001},
date = {2001-01-01},
journal = {JOURNAL OF MATERIALS SCIENCE},
volume = {36},
number = {24},
pages = {5853-5860},
abstract = {Metallic foam-filled tubes and their empty counterparts have been tested
at quasi-static and dynamic strain rates in order to determine their
energy absorption capabilities. Data from the Split-Hopkinson Pressure
Bar have been used to generate force vs. displacement curves that are
somewhat analogous to pseudo-engineering stress-strain curves. Force
balance calculations have also been made. These results indicate that,
on an equal weight basis, foam-filled tubes offer greater energy
absorption capability than empty tubes at quasi-static strain rates.
However, the benefit of foam filling does not appear to be extended to
strain rates of the order of 200-500 s(-1). Force balance calculations
are shown to have potential as a method for monitoring the crushing of
metallic foams at high strain rate. (C) 2001 Kluwer Academic Publishers.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Metallic foam-filled tubes and their empty counterparts have been tested
at quasi-static and dynamic strain rates in order to determine their
energy absorption capabilities. Data from the Split-Hopkinson Pressure
Bar have been used to generate force vs. displacement curves that are
somewhat analogous to pseudo-engineering stress-strain curves. Force
balance calculations have also been made. These results indicate that,
on an equal weight basis, foam-filled tubes offer greater energy
absorption capability than empty tubes at quasi-static strain rates.
However, the benefit of foam filling does not appear to be extended to
strain rates of the order of 200-500 s(-1). Force balance calculations
are shown to have potential as a method for monitoring the crushing of
metallic foams at high strain rate. (C) 2001 Kluwer Academic Publishers. |
2000
|
Hall, IW; Guden, M; Yu, CJ Crushing of aluminum closed cell foams: Density and strain rate effects Journal Article SCRIPTA MATERIALIA, 43 (6), pp. 515-521, 2000, ISSN: 1359-6462. Links | BibTeX @article{ISI:000089373000007,
title = {Crushing of aluminum closed cell foams: Density and strain rate effects},
author = {IW Hall and M Guden and CJ Yu},
doi = {10.1016/S1359-6462(00)00460-7},
issn = {1359-6462},
year = {2000},
date = {2000-08-01},
journal = {SCRIPTA MATERIALIA},
volume = {43},
number = {6},
pages = {515-521},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Guden, M; Hall, IW High strain rate deformation behavior of a continuous fiber reinforced
aluminum metal matrix composite Journal Article COMPUTERS & STRUCTURES, 76 (1-3), pp. 139-144, 2000, ISSN: 0045-7949, (Conference of the NATO-Advanced-Study-Institue on Mechanics of Composite
Materials and Structures, TROIA, PORTUGAL, JUL 12-24, 1998). Abstract | Links | BibTeX @article{ISI:000086637000014,
title = {High strain rate deformation behavior of a continuous fiber reinforced
aluminum metal matrix composite},
author = {M Guden and IW Hall},
doi = {10.1016/S0045-7949(99)00158-3},
issn = {0045-7949},
year = {2000},
date = {2000-06-01},
journal = {COMPUTERS & STRUCTURES},
volume = {76},
number = {1-3},
pages = {139-144},
organization = {NATO, Inst Adv Study; IDMEC; Inst Mech Engn; Inst Super Tecn; Tech Univ
Lisbon},
abstract = {An aluminum metal matrix composite reinforced with continuous
unidirectional alpha-Al2O3 fibers has been compression tested at
quasi-static and dynamic strain rates. In the transverse direction, the
composite showed increased flow stress and maximum stress within the
studied strain rate regime, 10(-3) to 3500 s(-1). The strain rate
sensitivity of the flow stress in this direction was found to be similar
to that of a similar, but unreinforced, alloy determined from previous
work. In the longitudinal direction, the maximum stress of the composite
increased with increasing strain rate within the range 10(-5) to 700
s(-1). The strain rate dependent maximum stress in this direction was
described by the strain rate dependent fiber buckling stress. (C) 2000
Elsevier Science Ltd. All rights reserved.},
note = {Conference of the NATO-Advanced-Study-Institue on Mechanics of Composite
Materials and Structures, TROIA, PORTUGAL, JUL 12-24, 1998},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
An aluminum metal matrix composite reinforced with continuous
unidirectional alpha-Al2O3 fibers has been compression tested at
quasi-static and dynamic strain rates. In the transverse direction, the
composite showed increased flow stress and maximum stress within the
studied strain rate regime, 10(-3) to 3500 s(-1). The strain rate
sensitivity of the flow stress in this direction was found to be similar
to that of a similar, but unreinforced, alloy determined from previous
work. In the longitudinal direction, the maximum stress of the composite
increased with increasing strain rate within the range 10(-5) to 700
s(-1). The strain rate dependent maximum stress in this direction was
described by the strain rate dependent fiber buckling stress. (C) 2000
Elsevier Science Ltd. All rights reserved. |
1998
|
Guden, M; Hall, IW High strain rate properties of an SiCW/2124-T6 aluminum composite at
elevated temperatures Journal Article SCRIPTA MATERIALIA, 39 (3), pp. 261-267, 1998, ISSN: 1359-6462. Links | BibTeX @article{ISI:000075059600001,
title = {High strain rate properties of an SiCW/2124-T6 aluminum composite at
elevated temperatures},
author = {M Guden and IW Hall},
doi = {10.1016/S1359-6462(98)00169-9},
issn = {1359-6462},
year = {1998},
date = {1998-07-01},
journal = {SCRIPTA MATERIALIA},
volume = {39},
number = {3},
pages = {261-267},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
|
Guden, M; Hall, IW Quasi-static and dynamic compression behaviour of an FP (TM)
alumina-reinforced aluminium metal matrix composite Journal Article JOURNAL OF MATERIALS SCIENCE, 33 (13), pp. 3285-3291, 1998, ISSN: 0022-2461. Abstract | Links | BibTeX @article{ISI:000077590800008,
title = {Quasi-static and dynamic compression behaviour of an FP (TM)
alumina-reinforced aluminium metal matrix composite},
author = {M Guden and IW Hall},
doi = {10.1023/A:1013272910939},
issn = {0022-2461},
year = {1998},
date = {1998-07-01},
journal = {JOURNAL OF MATERIALS SCIENCE},
volume = {33},
number = {13},
pages = {3285-3291},
abstract = {An aluminium metal matrix composite reinforced with continuous
unidirectional alpha-alumina fibres has been compression tested at
quasi-static and dynamic strain rates. In the transverse direction, the
composite showed increasing flow stress (at 5% strain) and maximum
stress within the studied strain rates, 10(-3)-3 x 10(3) s(-1). In the
longitudinal direction, the maximum stress of the composite increased
similarly with increasing strain rates within the range 10(-5)-7 x 10(2)
s(-1). If is shown that, if brooming of the sam pie ends can be
suppressed, the failure stress of the composite in longitudinal
compression increases significantly. Metallographic observations reveal
the typical modes of damage initiation in the composite. (C) 1998 Kluwer
Academic Publishers.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
An aluminium metal matrix composite reinforced with continuous
unidirectional alpha-alumina fibres has been compression tested at
quasi-static and dynamic strain rates. In the transverse direction, the
composite showed increasing flow stress (at 5% strain) and maximum
stress within the studied strain rates, 10(-3)-3 x 10(3) s(-1). In the
longitudinal direction, the maximum stress of the composite increased
similarly with increasing strain rates within the range 10(-5)-7 x 10(2)
s(-1). If is shown that, if brooming of the sam pie ends can be
suppressed, the failure stress of the composite in longitudinal
compression increases significantly. Metallographic observations reveal
the typical modes of damage initiation in the composite. (C) 1998 Kluwer
Academic Publishers. |
