文献类型：期刊文献

中文题名：Effects of post annealing on the microstructure,precipitation behavior,and mechanical property of a(CoCrNi)_(94)Al_(3)Ti_(3)medium-entropy alloy fabricated by laser powder bed fusion

作者：Zhuang Li[1];Pengcheng Zhao[1];Tiwen Lu[1];Kai Feng[2];Yonggang Tong[3];Binhan Sun[1];Ning Yao[1];Yu Xie[1];Bolun Han[2];Xiancheng Zhang[1];Shantung Tu[1]

机构：[1]Key Laboratory of Pressure Systems and Safety,Ministry of Education,School of Mechanical and Power Engineering,East China University of Science and Technology,Shanghai 200237,China;[2]Shanghai Key Laboratory of Materials Laser Processing and Modification,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;[3]College of Automobile and Mechanical Engineering,Changsha University of Science and Technology,Changsha 410114,China

年份：2023

期号：4

起止页码：142

中文期刊名：Journal of Materials Science & Technology

外文期刊名：材料科学技术（英文版）

收录：CSTPCD;;Scopus;CSCD:【CSCD2023_2024】；PubMed;

基金：This work was financially supported by the National Natural Science Foundation of China(nos.52105144 and 51725503);the Shanghai Super Postdoctoral Incentive Plan(no.2020134);the China Postdoctoral Science Foundation(no.2021M701201).

语种：英文

中文关键词：Medium-entropy alloy;Additive manufacturing;Heat treatment;Strengthening mechanism;Microstructural evolution

摘要：The additive manufacturing of multi-principal element alloys has remarkable potential for industrial ap-plications.In this study,a(CoCrNi)_(94)Al_(3)Ti_(3)medium-entropy alloy(MEA)with adequate strength-ductility synergy was prepared via laser powder bed fusion.The microstructural evolution,mechanical property,and deformation mechanisms of the MEA were investigated after post annealing for a short period(0.5 h)at a temperature range of 773-1373 K using various microstructural characterization techniques and quantitative analysis.The static recrystallization temperature of the(CoCrNi)_(94)Al_(3)Ti_(3)MEA ranged from 973 to 1073 K.The average grain size first decreased and then increased,while the dislocation den-sity persistently decreased and texture gradually weakened with increasing annealing temperature.Cr-richσ-phase precipitates formed after 1073 K and then gradually dissolved at 1373 K,while Ni,Al,and Ti elements were aggregated to form a small amount of fine L1_(2)coherent precipitates with an aver-age diameter of approximately 70 nm at 1373 K.The evolution of the dislocation density,grain size,and precipitates significantly influenced the propensity of deformation twins and stacking faults,which consequently affected the strain hardening behavior and mechanical properties.The quantitative calcu-lation of strengthening mechanisms showed that dislocation strengthening played a dominant role at annealing temperatures below 1073 K,and it significantly weakened at 1373 K.Precipitation and grain boundary strengthening both markedly increased owing to the formation of precipitation particles and recrystallization-induced grain refinement after annealing at 1073 K.