Cu过渡层对直接激光沉积TC4/IN718双金属结构组织性能的影响  

Effect of Cu Interlayer on Microstructure and Properties of TC4/IN718 Bimetallic Structure Fabricated by Directed Laser Deposition

作　　者：王辰阳 邢飞 刘祥宇 卞宏友 徐国建 Wang Chenyang;Xing Fei;Liu Xiangyu;Bian Hongyou;Xu Guojian(School of Mechanical Engineering,Shenyang University of Technology,Shenyang 110870,China;Liaoning Additive Manufacturing Industry Technology Research Institute,Shenyang 110200,China;School of Materials Science and Engineering,Shenyang University of Technology,Shenyang 110870,China)

机构地区：[1]沈阳工业大学机械工程学院,辽宁沈阳110870 [2]辽宁增材制造产业技术研究院,辽宁沈阳110200 [3]沈阳工业大学材料科学与工程学院,辽宁沈阳110870

出　　处：《稀有金属材料与工程》2023年第1期323-331,共9页Rare Metal Materials and Engineering

基　　金：辽宁省“兴辽英才计划”项目(XLYC1902022);辽宁省高校创新人才项目(202114027)。

摘　　要：钛合金和镍基合金各具有独特性能,二者的双金属结构在航空航天领域具有广泛的应用前景。由于2种金属的物理与化学性能差异较大,易在结合区域产生开裂。基于直接激光沉积(DLD)技术,分别制备了无过渡层和Cu过渡层的TC4/IN718双金属结构。测试分析结果表明,无过渡层双金属结构,结合区形成大量Ti-Ni脆性相,导致裂纹敏感性提高,产生开裂;Cu过渡层的双金属结构,在TC4与IN718之间形成Cu过渡区,限制TC4与IN718直接结合,降低裂纹敏感性,无裂纹等冶金缺陷产生,由于冶金反应与元素扩散的发生,在Cu过渡区中形成了少量Ti-Cu与微量Ti-Ni化合物相;化合物相在双金属结构中的产生,使Cu过渡区维氏硬度最高约为5801.6 MPa,但远低于无过渡层双金属结构的维氏硬度(最高约为8281 MPa)。Titanium alloys and nickel-based alloys have unique properties.The bimetallic structure formed by them has a broad application prospect in the aerospace field.However,due to the large differences in physical and chemical properties between the two metals,cracking is easy to occur at the bonding zone.Based on directed laser deposition(DLD)technology,TC4/IN718 bimetallic structures without interlayer and Cu interlayer were fabricated.The results of test and analysis results indicate that the TC4/IN718 bimetallic structure without interlayer has cracking due to the formation of the Ti-Ni brittle phases at the bonding zone,which leads to the increase of crack sensitivity.In the bimetallic structure with Cu interlayer,the Cu transition zone is formed between TC4 and IN718,which inhibits the direct combination of TC4 and IN718,reduces the crack sensitivity,and there is no metallurgical defects such as cracks.Due to metallurgical reaction and element diffusion,a small amount of Ti-Cu and a very small amount of Ti-Ni compound phases are formed in the Cu transition zone.Due to the formation of the compound phase,the Vickers hardness of the transition zone of TC4/IN718 bimetallic structure with Cu interlayer is about 5801.6 MPa.However,it is much lower than the Vickers hardness of the bonding zone of TC4/IN718 bimetallic structure without Cu interlayer(about 8281 MPa at most).

关 键 词：直接激光沉积 双金属结构 钛合金 镍基高温合金 微观组织 

分 类 号：TB331[一般工业技术—材料科学与工程]