TY - JOUR
T1 - Microstructural Effects on Damage Nucleation in Shock-Loaded Polycrystalline Copper
AU - Brown, Andrew David
AU - Wayne, Leda
AU - Pham, Quan
AU - Krishnan, Kapil
AU - Peralta, Pedro
AU - Luo, Sheng Nian
AU - Patterson, Brian M.
AU - Greenfield, Scott
AU - Byler, Darrin
AU - McClellan, Kenneth J.
AU - Koskelo, Aaron
AU - Dickerson, Rob
AU - Xiao, Xianghui
N1 - Funding Information:
This research work was funded by LANL under LDRD # 20060021DR, and by the Department of Energy, NNSA, under SSAA Grants # DE-FG52- 06NA26169, DE-FG52-10NA29653., and DE-NA0002005 and APS General User Proposal 35561. Eric Loomis, Pat Dickerson (LANL), Damian Swift (LLNL), David Wright, and Dallas Kingsbury (ASU) are thanked for their help during the various phases of the research work. Access to the TRIDENT Facility & Electron Microscopy Laboratory at LANL, Pavel Shevchenko at APS 2-BM, as well as the Center for High-Resolution Electron Microscopy and the Mechanical Testing Laboratory at ASU is gratefully acknowledged.
Publisher Copyright:
© 2014, The Minerals, Metals & Materials Society and ASM International.
PY - 2015/10/2
Y1 - 2015/10/2
N2 - Polycrystalline copper samples with varying thermomechanical histories were shock loaded to induce spall via laser-driven plate impacts at low shock stress (<6 GPa). Electron backscattering diffraction was used to obtain statistics on grain boundary (GB) misorientations within the spall plane and at all GBs that contained damage. Specimens with pre-existing plastic deformation showed dominant intergranular damage at boundaries in the 25 to 50 deg misorientation range, while heat-treated samples had mixed trans- and intergranular damage with a lessened misorientation influence at damaged GBs. 3-D X-ray tomography data were used to analyze global volume statistics and qualitatively inspect the shape of voids present in samples of varying thermomechanical histories. It was found that annealed samples had a mixed mode of spherical- and sheet-like voids, indicative of trans- and intergranular damage, respectively, and the microstructure with the highest number of Σ3 twin boundaries had the highest concentration of spherical voids. Data from a plastically pre-strained sample showed a dominance of needle- and sheet-like voids, indicating primarily intergranular damage due to the higher strength of the bulk material forcing the damage to nucleate at weaker defects, in this case GBs.
AB - Polycrystalline copper samples with varying thermomechanical histories were shock loaded to induce spall via laser-driven plate impacts at low shock stress (<6 GPa). Electron backscattering diffraction was used to obtain statistics on grain boundary (GB) misorientations within the spall plane and at all GBs that contained damage. Specimens with pre-existing plastic deformation showed dominant intergranular damage at boundaries in the 25 to 50 deg misorientation range, while heat-treated samples had mixed trans- and intergranular damage with a lessened misorientation influence at damaged GBs. 3-D X-ray tomography data were used to analyze global volume statistics and qualitatively inspect the shape of voids present in samples of varying thermomechanical histories. It was found that annealed samples had a mixed mode of spherical- and sheet-like voids, indicative of trans- and intergranular damage, respectively, and the microstructure with the highest number of Σ3 twin boundaries had the highest concentration of spherical voids. Data from a plastically pre-strained sample showed a dominance of needle- and sheet-like voids, indicating primarily intergranular damage due to the higher strength of the bulk material forcing the damage to nucleate at weaker defects, in this case GBs.
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U2 - 10.1007/s11661-014-2482-z
DO - 10.1007/s11661-014-2482-z
M3 - Article
AN - SCOPUS:84940721850
SN - 1073-5623
VL - 46
SP - 4539
EP - 4547
JO - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
JF - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
IS - 10
ER -