Refined microstructure and enhanced mechanical properties of AlCrFe_(2)Ni_(2) medium entropy alloy produced via laser remelting

作     者：Tianyi Han Yong Liu Mingqing Liao Danni Yang Nan Qu Zhonghong Lai Jingchuan Zhu Tianyi Han;Yong Liu;Mingqing Liao;Danni Yang;Nan Qu;Zhonghong Lai;Jingchuan Zhu

作者机构：School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China National Key Laboratory for Precision Hot Processing of MetalsHarbin Institute of TechnologyHarbin 150001China Center of Analysis and Measurement and ComputingHarbin Institute of TechnologyHarbin 150001China 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2022年第99卷第4期

页      面：18-27页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

主　　题：Medium entropy alloy Laser remelting Microstructure Nano-indentation Strengthening mechanism 

摘      要：A Co-free as-cast AlCrAlCrFe_(2)Ni_(2)medium entropy alloy(MEA)with multi-phases was remelted by fiber laser in this *** effect of laser remelting on the microstructure,phase distribution and mechanical properties was investigated by characterizing the as-cast and the remelted AlCrAlCrFe_(2)Ni_(2)*** laser remelting process resulted in a significant decrease of grain size from about 780μm to 58.89μm(longitudinal section)and 15.87μm(transverse section)and an increase of hardness from 4.72±0.293 GPa to 6.40±0.147 GPa(longitudinal section)and 7.55±0.360 GPa(transverse section).It was also found that the long side plate-like microstructure composed of FCC phase,ordered B2 phase and disordered BCC phase in the as-cast alloy was transformed into nano-size weave-like microstructure consisting of alternating ordered B2 and disordered BCC *** mechanical properties were evaluated by the derived stressstrain relationship obtained from nano-indentation tests *** results showed that the yield stress increased from 661.9 MPa to 1347.6 MPa(longitudinal section)and 1647.2 MPa(transverse section)after *** individual contribution of four potential strengthening mechanisms to the yield strength of the remelted alloy was quantitatively evaluated,including grain boundary strengthening,dislocation strengthening,solid solution strengthening and precipitation *** calculation results indicated that dislocation and precipitation are dominant strengthening mechanisms in the laser remelted MEA.