The influence of nanosized precipitates on Portevin-Le Chatelier bands and surface roughness in AlMgScZr alloy  

作　　者：Yaoxiang Duan Han Chen Zhe Chen Lei Wang Mingliang Wang Jun Liu Fengguo Zhang Haowei Wang 

机构地区：[1]State Key Laboratory of Metal Matrix Composites,Shanghai Jiao Tong University,Shanghai,200240,China [2]School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai,200240,China

出　　处：《Journal of Materials Science & Technology》2021年第28期74-82,共9页材料科学技术（英文版）

基　　金：financially supported by the Natural Science Foundation of China(Nos.51971137,11875192,and U1930101)。

摘　　要：The influence of different precipitate-dislocation interactions,namely dislocation shearing and bypassing mechanisms,on PLC bands and the resultant surface roughness in AlMgScZr alloy was investigated.Three-dimensional surface roughness was quantitatively measured by confocal microscopy.We find that the introduction of shearable precipitates increases the stress amplitude,decreases the PLC bands number and surface roughness.However,the stress amplitude decreases,the PLC bands number and surface roughness increase with shearable precipitates turning to nonshearable precipitates.By analyzing the precipitation strengthening mechanisms quantitatively,the influence of precipitates on PLC bands and the resultant surface roughness was explored.Furthermore,our study demonstrates that the shearable precipitates can decrease the surface roughness by decreasing the number of PLC bands,which is instructive for designing structural materials with desirable mechanical property and surface quality.

关 键 词：Aluminum alloys Precipitate-dislocation interaction Portevin-Le Chatelier Stress amplitude Surface roughness 

分 类 号：TG146.21[一般工业技术—材料科学与工程]