铝合金CMT熔敷工艺对添加Nb中间层钛/铝构件成形及组织的影响  

Effect of CMT deposition processes of Al alloy on the forming and microstructure of Ti/Al dissimilar materials with Nb interlayer

作　　者：张超 吴定勇 杨辉 许乃强 申俊琦[2,3] 梁瑛 ZHANG Chao;WU Dingyong;YANG Hui;XU Naiqiang;SHEN Junqi;LIANG Ying(Tianhe Mechanical Equipment Manufacturing Co.,Ltd.,Suzhou 215500,Jiangsu pro.,China;School of Materials Science and Engineering,Tianjin University,Tianjin 300354,China;Tianjin Key Laboratory of Advanced Joining Technology,Tianjin University,Tianjin 300354,China)

机构地区：[1]中交天和机械设备制造有限公司,江苏苏州215500 [2]天津大学材料科学与工程学院,天津300354 [3]天津大学天津市现代连接技术重点实验室,天津300354

出　　处：《焊接技术》2022年第8期1-6,I0007,共7页Welding Technology

摘　　要：针对钛/铝异种材料构件的高质量制备需求,采用基于冷金属过渡(CMT)技术的电弧增材制造(WAAM)方法制备出添加Nb中间层的钛/铝构件,研究了铝合金熔敷送丝速度对构件成形与组织的影响规律。结果表明,随着铝合金熔敷送丝速度由3 m/min提高至5 m/min,一个CMT周期内的峰值阶段持续时间延长,热输入增大,铝合金熔敷层宽度增加;送丝速度为3 m/min和4 m/min时,在铝合金熔敷层与钛合金熔敷层之间均剩余了一层纯Nb中间层,在Al/Nb界面处分别形成了厚度约为0.8μm和2.0μm的AlNb反应层;送丝速度为5 m/min时,Nb中间层和部分钛合金熔敷层发生了熔化,形成了Ti-Al, Al-Nb和Ti-Cu等多种脆性金属间化合物。选择4 m/min送丝速度进行铝合金熔敷,可以获得具有较好成形和组织分布的添加Nb中间层钛/铝异种材料构件。Aiming at the demand for high-quality manufacturing of Ti/Al dissimilar components,wire and arc additive manufacturing( WAAM) technology based on cold metal transfer( CMT) was applied to fabricate the Ti/Al dissimilar samples with Nb interlayer.The effect of wire feeding speed for Al alloy deposition on forming and microstructure of the samples was investigated.The results showed that the duration time of the peak phase in a CMT cycle increased with the increase of the wire feeding speed from 3 m/min to 5 m/min,leading to the increase of the heat input and therefore the wider Al deposition layer.When the wire feeding speed were 3 m/min and 4 m/min,a Nb interlayer could be retained between the Al deposition layer and Ti deposition layer,and a AlNb reaction layer with the thickness of 0.8 μm and2.0 μm were formed at the Al/Nb interface respectively.When the wire feeding speed was 5 m/min,the Nb interlayer and partial Ti deposition layer were melted during the deposition process of Al alloy,resulting in the formation of Ti-Al,Al-Nb and Ti-Cu brittle intermetallic compounds.The Ti/Al dissimilar component containing Nb interlayer with good forming and appropriate microstructure could be obtained when the wire feeding speed for Al alloy deposition was4 m/min.

关 键 词：冷金属过渡 电弧增材制造 钛/铝异种材料 中间层 成形与组织 

分 类 号：TG455[金属学及工艺—焊接]