Effect of CoCrFeNiMn high entropy alloy interlayer on microstructure and mechanical properties of laser-welded NiTi/304 SS joint
Effect of CoCrFeNiMn high entropy alloy interlayer on microstructure and mechanical properties of laser-welded NiTi/304 SS joint
复制标题
CoCrFeNiMn高熵合金中间层对NiTi/304不锈钢激光焊接接头显微组织和力学性能的影响
DOI：
10.1016/j.jmrt.2022.03.022
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Wenbin Zhong
中科院分区：
文献类型：
--
作者：
Hongwei Wang;Jilin Xie;Yuhua Chen;Wenkuo Liu;Wenbin Zhong
为了抑制NiTiSMA/304 SS激光焊接接头中Fe-Ti IMC的形成，改善接头性能。本研究采用显微激光焊接技术，对NiTiSMA/304 SS异种合金接头进行了CoCrFeNiMn高熵合金中间层焊接。系统研究了CoCrFeNiMn高熵合金中间层对NiTiSMA/304 SS激光焊接接头组织和性能的影响。结果表明，HEA中间层的加入显著减少了FeTi相等脆性金属间化合物(IMCs)的生成。高熵合金中间层的加入促进了(Fe，Ni)固溶体相的形成，因此与HEA中间层的接头由(Fe，Ni)固溶体和少量FeTiIMCs和B2相组成。加入HEA中间层后，焊缝金属的平均显微硬度由732HV降至221HV。HEA夹层的加入显著改善了接头的拉伸剪切性能，接头的拉剪载荷可达175N，是不加夹层的接头的6倍。
In order to suppress the formation of Fe-Ti IMCs in NiTi SMA/304 SS laser-welded joint and improve the properties of the joint. In this study, NiTi SMA/304 SS dissimilar alloys joints with and without CoCrFeNiMn high entropy alloy interlayer were obtained by micro laser welding process. The effect of CoCrFeNiMn high entropy alloy interlayer on the microstructure and properties of NiTi SMA/304 SS laser-welded joint was investigated systematically. Results showed that the addition of HEA interlayer significantly reduced the formation of the brittle intermetallic compounds (IMCs) such as FeTi phase. The addition of high entropy alloy interlayer promotes the formation of (Fe,Ni) solid solution phase, therefor, the joint with HEA interlayer is composed of (Fe,Ni) solid solution and small amount of FeTi IMCs and B2 phase. On the other hand, the average microhardness of weld metal was decreased from 732 HV to 221 HV by adding the HEA interlayer. The addition of HEA interlayer significantly improves the tensile shear properties of the joint, and the tensile shear load of the joint can reached 175 N, which is 6 times higher than that of the joint without HEA interlayer.