TY - JOUR
T1 - The mechanical properties of single-crystal and ultrananocrystalline diamond
T2 - A theoretical study
AU - Paci, Jeffrey T.
AU - Belytschko, Ted
AU - Schatz, George C.
N1 - Funding Information:
We gratefully acknowledge the grant support from the National Science Foundation (Grant CMS 500304472) and NASA University Research, Engineering and Technology Institute on Bio Inspired Materials (BIMat) under Award No. NCC-1-02037.
PY - 2005/10/14
Y1 - 2005/10/14
N2 - We examine the mechanical properties of single-crystal and ultrananocrystalline diamond (UNCD) by simulating their fracture using semiempirical quantum mechanics and density functional theory. Our results predict a failure strain of 0.13 and a fracture stress of 100 GPa for UNCD, which are 37% and 43%, respectively, that of single-crystal diamond. The Young's modulus of UNCD is E = 1.05 TPa which is only slightly smaller than that of single-crystal diamond (E = 1.09 TPa). The UNCD fracture stress value (σf = 100 GPa) is very large compared to that observed experimentally (σf < 5 GPa). We use Griffith theory to show that this difference is due to defects in UNCD.
AB - We examine the mechanical properties of single-crystal and ultrananocrystalline diamond (UNCD) by simulating their fracture using semiempirical quantum mechanics and density functional theory. Our results predict a failure strain of 0.13 and a fracture stress of 100 GPa for UNCD, which are 37% and 43%, respectively, that of single-crystal diamond. The Young's modulus of UNCD is E = 1.05 TPa which is only slightly smaller than that of single-crystal diamond (E = 1.09 TPa). The UNCD fracture stress value (σf = 100 GPa) is very large compared to that observed experimentally (σf < 5 GPa). We use Griffith theory to show that this difference is due to defects in UNCD.
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U2 - 10.1016/j.cplett.2005.08.019
DO - 10.1016/j.cplett.2005.08.019
M3 - Article
AN - SCOPUS:25844530154
VL - 414
SP - 351
EP - 358
JO - Chemical Physics Letters
JF - Chemical Physics Letters
SN - 0009-2614
IS - 4-6
ER -