的應(yīng)力晶化行為
(中國科學(xué)技術(shù)大學(xué) 中科院材料力學(xué)行為和設(shè)計(jì)重點(diǎn)實(shí)驗(yàn)室，合肥 230026)
摘 要: 采用Mishin鑲嵌原子勢(shì)，通過分子動(dòng)力學(xué)方法模擬金屬玻璃在壓痕過程中的晶化行為，從微觀結(jié)構(gòu)演化的角度考察應(yīng)力晶化過程中晶粒的形核、長大與合并的過程。局部較大剪切應(yīng)力導(dǎo)致內(nèi)部臨近的非晶原子形成晶核，發(fā)生晶粒生長與合并的區(qū)域與Hertz理論符合。最終生成的晶粒具有面心立方結(jié)構(gòu)，其(111)方向平行于剪切面。計(jì)算結(jié)果與文獻(xiàn)中的實(shí)驗(yàn)現(xiàn)象一致，并且符合最小能量準(zhǔn)則。
關(guān)鍵字: 金屬玻璃；應(yīng)力晶化；分子動(dòng)力學(xué)；壓痕
crystallization behavior during indentation for metallic glass
（CAS Key Laboratory of Mechanical Behavior and Design of Materials,University of Science and Technology of China, Hefei 230026, China）
Abstract:The stress-induced crystallization behavior was simulated during the indentation deformation process for metallic glass copper using molecular dynamics method. The Mishin embedded atom method (EAM) was adopted as the interaction among atoms in the system. The nucleation, growth and coalescence of crystal grains were investigated through the evolution of microstructure. The local shear stress of amorphous system makes neighboring atoms nucleate. The site of growth and coalescence of crystal grains agrees well with the Hertz theory. The final crystalline phase has a FCC structure and the (111) plane is parallel to the shear direction. The computational result is consistent with the reported experiment phenomena and the minimum energy principle.
Key words: metallic glass; stress-induced crystallization; molecular dynamics; indentation
