热处理对激光熔化沉积TC17钛合金显微组织及力学性能的影响  

Effect of Heat Treatment on Microstructure and Mechanical Properties of Laser Melting Deposited TC17 Titanium Alloy

作　　者：陈博[1] 邵冰[2] 刘栋[1] 田象军[1] 刘长猛[1] 王华明[1] 

机构地区：[1]北京航空航天大学激光材料制备与成形实验室,北京100191 [2]中国人民解放军海军驻沈阳地区军事代表室,辽宁沈阳110000

出　　处：《中国激光》2014年第4期49-55,共7页Chinese Journal of Lasers

基　　金：国家973计划(2010CB731705)

摘　　要：激光熔化沉积(LMD)TC17钛合金在航空航天领域具有广阔的应用前景,其沉积态试样强度较高但塑性较差,为了改善其综合力学性能,首先对LMD TC17钛合金进行退火处理,结果表明随退火温度升高α相含量逐渐减小,α片层粗化,塑性升高而强度下降,且退火后LMD TC17钛合金拉伸性能未达到盘件技术标准。进一步研究固溶时效对其组织性能的影响,固溶温度升高将使初生α相(αP)相含量降低、αP片层粗化;时效温度升高使次生α相(αS)粗化。拉伸性能受αP、αS相含量、α片层厚度等因素影响,β基体上均匀弥散析出细小αS的组织将有利于提高强度,αP含量增加、组织粗化有利于提高塑性,通过800℃/4h固溶处理后水淬以及630℃/8h空冷热处理可以使LMD TC17钛合金获得较优的强塑性匹配,拉伸性能达到盘件技术标准。Laser melting deposited （LMD） TC17 titanium alloy has a vast application prospect in aerospace industries. The mechanical properties of LMD TC17 as-deposited alloy exhibits excellent strength yet lower ductility. Therefore, in an attempt to improve the mechanical properties, anneal treatment for LMD TC17 alloy is firstly studied. The volume fraction of primary a phase （ap） decreases and a lath coarsens with rising temperature, which is good for ductility but harmful for strength. Anneal treated LMD TC17 alloy cannot obtain optimistical combination of strength and ductility to conform to disk technical standard. The effect of solution-aging treatment on microstructure and mechanical properties of LMD TC17 alloy is further studied. The volume fraction of ap increases and a lath coarsens with solution temperature rising, and as coarsens obviously when aged at high temperature. The mechanical properties are sensitive to volume fraction of am and as, as well as width of a lath. The ultra fine as precipitation in fl matrix results in high strength. Coarsening a lath and increasing volume fraction of ap are helpful for ductility. After, annealing and water quenching, which conform to the disk technical standard.

关 键 词：激光技术 激光熔化沉积 TC17钛合金 热处理 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]