选择性激光熔化打印等原子比NiCoCr中熵合金力学性能与温度的相关性  

Temperature dependence of mechanical properties of equiatomic NiCoCr medium-entropy alloy printed by selective laser melting

作　　者：罗亚君 张卫东 彭飞 刘胜 李忠涛 吴正刚 Ya-jun LUO;Wei-dong ZHANG;Fei PENG;Sheng LIU;Zhong-tao LI;Zheng-gang WU(College of Materials Science and Engineering,Hunan University,Changsha 410082,China;Hunan Engineering Research Center of New Energy Vehicle Lightweight,Hunan Institute of Engineering,Xiangtan 411104,China)

机构地区：[1]湖南大学材料科学与工程学院,长沙410082 [2]湖南工程学院新能源汽车轻量化湖南省工程研究中心,湘潭411104

出　　处：《Transactions of Nonferrous Metals Society of China》2024年第5期1547-1557,共11页中国有色金属学报（英文版）

基　　金：National Natural Science Foundation of China(No.51904100);Natural Science Foundation of Hunan Province,China(No.2021JJ40101)。

摘　　要：研究工艺参数对选择性激光融化制备的等原子比NiCoCr中熵合金致密度、显微组织和力学性能的影响,以及该合金的力学性能与温度的相关性。结果表明,显微组织和力学性能不与激光的体积能量密度呈线性相关,其主要是受扫描速度和激光功率影响。扫描速度为800 mm/s且激光功率为250W为最佳的工艺参数,但是在该工艺参数下的体积能量密度仅为57 J/mm^(3),低于最高能量密度68 J/mm^(3)。以最佳工艺制备的样品在77、200和293 K温度下测得的屈服强度分别为~819、~709和~618 MPa。通过计算揭示力学性能的温度相关性方程,并得到实验验证。The effects of process parameters on the densification,microstructures,and mechanical properties,as well as the temperature dependence of the mechanical properties,of a NiCoCr medium-entropy alloy fabricated with selective laser melting were studied.The results indicate that the microstructures and mechanical properties are not linearly related to the volume energy density(VED)but are affected by the scanning speed and laser power.The optimal process parameters are identified as a scanning speed of 800 mm/s and a laser power of 250 W,while the VED is only 57 J/mm^(3) lower than the highest value of 68 J/mm^(3).The yield strengths of the optimal sample are~819,~709 and~618 MPa at 77,200,and 293 K,respectively.The temperature dependence of the mechanical properties is determined and verified by the experimental results.

关 键 词：选择性激光熔化 中熵合金 NiCoCr 低温 力学性能 

分 类 号：TG139[一般工业技术—材料科学与工程] TG665[金属学及工艺—合金]