文献类型：期刊文献

英文题名：From continuum to quantum mechanics study on the fracture of nanoscale notched brittle materials

作者：Wang, Xiaoyuan[1];Xiang, Mingzhi[1];Yin, Meng[1];Yan, Yabin[1];Xuan, Fuzhen[1]

机构：[1]East China Univ Sci & Technol, Sch Mech Power & Engn, Key Lab Pressure Syst & Safety, Minist Educ, Shanghai 200237, Peoples R China

年份：2021

卷号：199

外文期刊名：INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES

收录：;EI(收录号：20211510188018);WOS:【SCI-EXPANDED(收录号:WOS:000647692500004)】；

基金：This work was supported by Natural Science Foundation of Shanghai (Grant No. 19ZR1413200) , Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, National Natural Science Foundation of China (Grant Nos. 51835003, 11602252) .

语种：英文

外文关键词：Nanoscale; Fracture energy; In situ TEM experiment; Cohesive zone model; First-principles calculations; Silicon

摘要：The fracture of nanoscale notched brittle materials is investigated using the mull-scale analysis of cohesive zone modeling and first-principles calculations based on the notched nano-cantilever bending experiment. The fracture of nanoscale single-crystal silicon is achieved at the nano-notch tip, and the load-deflection curve is obtained during in situ TEM experiment. On the other hand, a bilinear CZM is adopted to simulate the observed fracture from the notch tip due to the stress concentration of less than 1 nm. The CZM parameters determined from one specimen, phi(n)=9.78 J/m(2), sigma(max) = 13.04 GPa, and Delta(c)(n)=1.5 nm, accurately predict the fracture behaviors of all other specimens regardless of specimen sizes, indicating the robust applicability of CZM for describing the fracture of nanoscale brittle materials. In addition, first-principles calculations are performed to investigate the inherent fracture properties of single-crystal silicon from atomic and electronic viewpoints. The fracture surface energy and critical bond length for the break of atomic bonds during the fracture are compared with the cohesive energy and failure length parameter, respectively, which provides the atomistic interpretation of CZM validity for the fracture of brittle materials by the extremely small stress concentration. Finally, the comparison of cohesive energy with the fracture energy obtained by fracture mechanics of nanoscale and bulk single-crystal silicon indicates that the consumed energy is an effective linkage to quantify the fracture of brittle materials at different scales.