QQ客服 官方微博 反馈留言

	Interfacial diffusion aided deformation during nanoindentation
	Samanta, Amit ; Weinan, E.
	2016
关键词	DISLOCATION NUCLEATION INCIPIENT PLASTICITY MICRO-INDENTATION DEPTH DEPENDENCE FREE-ENERGY MECHANISMS CRYSTALS SURFACES VOLUME CREEP
英文摘要	Nanoindentation is commonly used to quantify the mechanical response of material surfaces. Despite its widespread use, a detailed understanding of the deformation mechanisms responsible for plasticity during these experiments has remained elusive. Nanoindentation measurements often show stress values close to a material's ideal strength which suggests that dislocation nucleation and subsequent dislocation activity dominates the deformation. However, low strain-rate exponents and small activation volumes have also been reported which indicates high temperature sensitivity of the deformation processes. Using an order parameter aided temperature accelerated sampling technique called adiabatic free energy dynamics [J. B. Abrams and M. E. Tuckerman, J. Phys. Chem. B, 112, 15742 (2008)], and molecular dynamics we have probed the diffusive mode of deformation during nanoindentation. Localized processes such as surface vacancy and ad-atom pair formation, vacancy diffusion are found to play an important role during indentation. Our analysis suggests a change in the dominant deformation mode from dislocation mediated plasticity to diffusional flow at high temperatures, slow indentation rates and small indenter tip radii. (C) 2016 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).; U.S. Department of Energy by Lawrence Livermore National Laboratory [DE-AC52-07NA27344]; U.S. Department of Energy [DE-SC0009248]; Office of Naval Research [N00014-13-1-0338]; SCI(E); EI; ARTICLE; weinan@math.princeton.edu; 7; 6
语种	英语
出处	EI ; SCI
出版者	AIP ADVANCES
内容类型	其他
源URL	[http://hdl.handle.net/20.500.11897/491912]
专题	数学科学学院
推荐引用方式 GB/T 7714	Samanta, Amit,Weinan, E.. Interfacial diffusion aided deformation during nanoindentation. 2016-01-01.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。