选区激光熔化制备Ti-3Cu合金的显微组织及力学性能  

Microstructure and Mechanical Properties of Ti-3Cu Alloy Fabricated by Selective Laser Melting

作　　者：汪亮亮 李姝 谭海兵 钟燕 田伟 刘振 朱昌洪 WANGLiangliang;LIShu;TANHaibing;ZHONGYan;TIANWei;LIUZhen;ZHUChanghong(China Aviation Gas Turbine Research Institute,Chengdu 610500,China)

机构地区：[1]中国航发四川燃气涡轮研究院,四川成都610500

出　　处：《热加工工艺》2025年第7期13-18,共6页Hot Working Technology

基　　金：航空发动机及燃气轮机重大专项项目(J2019-VI-0005-0119)。

摘　　要：以钛铜混合粉末为原材料,采用选区激光熔化制备了高性能Ti-3Cu(wt%)合金,然后分别进行800、1000℃保温2 h,空冷处理,重点研究了激光选区熔化的Ti-3Cu合金和1000℃热处理后合金的显微组织演化和力学性能。结果表明:选区激光熔化成型的Ti-3Cu合金微观组织均匀。Ti-3Cu合金在快冷条件下形成了板条状的α细晶组织,并且晶界处有明显的Cu偏聚,析出Ti_(2)Cu条带,有明显的界面钉扎效应,并与晶内的Ti_(2)Cu纳米颗粒共同作用,极大地增强Ti-3Cu合金的抗拉强度。Ti-3Cu合金在1000℃热处理后,晶粒长大,Cu元素在晶界处偏析形成大量脆硬的Ti_(2)Cu相,导致其强度降低。Ti-3Cu合金经800℃热处理,SLM过程中的应力集中有效降低,且未在晶界处析出大量的Ti_(2)Cu,较SLM样品,其强度降低,塑性升高。Taking the titanium-copper mixed powders as raw materials,the high-performance Ti-3Cu(wt%)alloy was fabricated by using selective laser melting(SLM),then the heat treatment was carried out at 800℃,1000℃for 2 h and air cooling,respectively.The microstructure evolution and mechanical properties of the SLMed Ti-3Cu alloy and the alloy after 1000℃heat treatment were mainly studied.The results show that the microstructure of the SLMed Ti-3Cu alloy is uniform.Under rapid cooling conditions,lamellarαfine-grain structure is formed in Ti-3Cu alloy,and there is significant accumulation of copper at the grain boundaries and Ti_(2)Cu band is precipitated,which has a pronounced interfacial pinning effect.The Ti_(2)Cu band and the intragranular Ti_(2)Cu nanoparticles significantly enhance the tensile strength of the alloy.After 1000℃heat treatment of Ti-3Cu alloy,the grains grow up,the Cu element segregation at the grain boundary forms a large amount of brittle hard Ti_(2)Cu phase,which makes the strength decrease.When the Ti-3Cu alloy is treated with 800℃,the stress concentration during SLM is effectively reduced,and no large amount of Ti_(2)Cu is precipitated at the grain boundary,the strength decreases and the plasticity increases compared with those of the SLMed sample.

关 键 词：钛合金 选区激光熔化 显微组织 力学性能 

分 类 号：TG146.23[一般工业技术—材料科学与工程] TG456.7[金属学及工艺—金属材料]