摘要
采用搅拌摩擦加工制备了以AlCoCrFeNi_(2.1)高熵合金为增强相的6061铝合金复合材料(AlCoCrFeNi_(2.1)/6061Al),重点研究了加工道次对复合材料组织均匀性、界面结合以及力学性能的影响。结果表明,随搅拌摩擦加工道次的增加,AlCoCrFeNi_(2.1)/6061Al复合材料组织均匀性及力学性能均得到明显改善.复合材料中基体与增强相界面结合良好,界面处扩散层厚度随加工道次增加而增大。相较于不添加增强相的6道次搅拌摩擦加工铝合金,AlCoCrFeNi_(2.1)增强相颗粒的引入可进一步细化晶粒并提高抗拉强度,且随着加工道次增加,复合材料抗拉强度及断后伸长率均显著升高。2,4道次下的断口存在明显的颗粒聚集区,而6道次下断口表面颗粒分布均匀且呈现大量韧窝,为典型的韧性断裂。该现象主要归因于载荷传递效应、弥散强化和细晶强化3大强化机制。
6061 aluminum alloy composites using AlCoCrFeNi_(2.1)high entropy alloy as reinforced phases were prepared by friction stir processing.The effect of processing pass on the microstructural uniformity,interfacial metallurgical bonding and mechanical properties of composites were mainly investigated.The results indicated that microstructural uniformity and mechanical properties of AlCoCrFeNi_(2.1)/6061Al composites were improved obviously with the increase of friction stir processing passes.The interface between matrix and reinforcements was well bonded with a certain diffusion layer in the composites.With the increase of processing passes,the thickness of the diffusion layer increased.Compared with 6-pass friction stir processed aluminum alloys without reinforced phases,the adding of AlCoCrFeNi_(2.1)particles can refine grain and enhance the tensile strength of composites.The tensile strength and elongation of composites increased markedly with the increase of processing passes.There are evident particles aggregation areas in the fracture surface of 2-pass and 4-pass samples,while the particles uniformly distribute and there are many dimples,presenting a ductile fracture mode on the fracture surface of 6-pass samples.The phenomena are attributed to three strengthening mechanisms of load transfer effect,dispersion strengthening and fine grain strengthening.
作者
李鹏
廉润康
马超群
董红刚
Li Peng;Lian Runkang;Ma Chaoqun;Dong Honggang(Dalian University of Technology,Dalian 116024,Liaoning,China)
出处
《机械制造文摘（焊接分册）》
2023年第4期25-33,共9页
Welding Digest of Machinery Manufacturing
基金
国家自然科学基金面上资助项目(52075074)。
关键词
高熵合金
搅拌摩擦加工
铝基复合材料
微观组织
力学性能
high entropy alloy
friction stir processing
aluminum matrix composites
microstructure
mechanical properties
