以机械搅拌法制备AlFeCrCoNi/Al的组织与力学性能研究

Microstructure and Mechanical Properties of AlFeCrCoNi/Al Matrix Composites Prepared by Mechanical Stirring Method

为了研究AlFeCrCoNi增强铝基复合材料的微观组织与退火状态下的力学性能,文中以机械搅拌法制备了AlFeCrCoNi/Al,利用光学显微镜和场发射扫描电镜对其宏观及微观形貌进行了观测;采用X射线衍射仪对其物相进行了表征与分析;利用布氏硬度机、阿基米德排水法和电子万能试验机对其力学性能进行了测量与分析。研究结果表明:在颗粒增强金属基复合材料的搅拌铸造制备过程中,实现颗粒均匀分布的一个关键因素是选择适当的增强颗粒含量,而增强颗粒的质量分数控制在10%以下时最为理想;随着高熵合金质量分数的增加,复合材料的致密度明显减小,而布氏硬度明显增加;质量分数为5%的AlFeCrCoNi增强铝基复合材料随着退火时间增加,抗拉强度逐渐增加;AlFeCrCoNi为增强相制备的Al基复合材料的断裂类型为韧性断裂,断裂机理为微孔聚集型断裂。

The paper focuses on the microstructure of AlFeCrCoNi high entropy alloy reinforced Al matrix composites prepared by mechanical stirring and their mechanical properties under annealing conditions.Their macroscopic and microscopic morphology was observed by optical microscopy and field emission scanning electron microscopy and their phase was characterized and analyzed by an X-ray diffraction instrument.Their mechanical properties were measured by a Brinell hardness tester,Archimedes drainage method and an electronic universal testing machine.The results show that in the stirring casting preparation of particle reinforced metal matrix composites,the key to achieving even distribution of particles is the appropriate particle content,and the ideal mass fraction of reinforced particles is less than 10%.With the increase of high entropy alloy mass fraction,the density of the composites decreases obviously and the Brinell hardness increases apparently.For the AlFeCrCoNi reinforced aluminum matrix composites whose mass fraction is 5%,their tensile strength increases gradually with the annealing time increasing.The fracture mode of AlFeCrCoNi high entropy alloy reinforced Al matrix composites is ductile fracture,and their fracture mechanism is micro aggregate fracture.