摘要
对近年来NiTi形状记忆合金与异种材料(不锈钢和钛合金)激光焊接的研究情况进行了总结分析。由于材料的化学成分差异很大,直接激光焊接在接头中极易生成脆性金属间化合物,使得力学性能严重恶化,限制了异种材料结构的应用。国内外关于优化NiTi形状记忆合金与异种材料的激光焊接接头力学性能的方法,主要包括添加中间层和激光偏置两种方法,它们的共同之处是都可以减少脆性金属间化合物生成,不同之处是采用添加中间层的方法在抑制金属间化合物产生的同时会在焊缝中引入新的金属间化合物,接头的力学性能取决于新引入金属间化合物的脆性,脆性低则接头的力学性能更好;另外,中间层的添加量不能过多,否则会恶化力学性能。对于激光偏置焊接法,激光的偏移位置和偏移量至关重要,该方法的优点是可以节省填充材料,但是对于装配精度要求较高。与激光偏置法相比,采用添加中间层的方法,接头的力学性能更好。除了以上两种方法外,焊后热处理也可以改善接头的力学性能。最后提出NiTi形状记忆合金与异种材料激光焊接未来可能的研究方向,旨在为后续研究提供参考与借鉴。
The laser welding of NiTi shape memory alloy with dissimilar materials(stainless steel and titanium alloy)in recent years is summarized and analyzed.Due to the great difference in chemical composition of materials,brittle intermetallic compounds easily generated in joints of direct laser welding.Which led to serious deterioration of mechanical properties and limited the application of heterogeneous materials.At home and abroad,the methods to optimize the mechanical properties of laser welded joints of NiTi shape memory alloy and dissimilar materials mainly included adding intermediate layer and laser bias.Their common point was that they can reduce the generation of brittle intermetallic compounds.The difference is that the method of adding intermediate layer can inhibit the generation of intermetallic compounds while introducing new intermetallic compounds into the weld.The mechanical properties of the joint depended on the brittleness of the new intermetallic compounds,and the mechanical properties of the joint are better if the brittleness is lower.In addition,the amount of intermediate layer should not be too much,otherwise it will deteriorate the mechanical properties.For laser bias welding,the position and distance of laser offset are very important.The advantage of this method is that filling materials can be saved,but the assembly accuracy is high.Compared with the laser bias method,the mechanical properties of the joint are better by adding an intermediate layer.In addition to the above two methods,post-weld heat treatment can also improve the mechanical properties of joints.Finally,the possible future research direction of laser welding between NiTi shape memory alloy and dissimilar materials is proposed to provide reference for subsequent research.
作者
成奇
郭宁
张迪
张帅
陈昊
何金龙
CHENG Qi;GUO Ning;ZHANG Di;ZHANG Shuai;CHEN Hao;HE Jinlong(State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150000;Shandong Provincial Key Laboratory of Special Welding Technology,Harbin Institute of Technology at Weihai,Weihai 264209;Shandong Institute of Shipbuilding Technology,Weihai 264209;School of Mechanical Engineering,Yanshan University,Qinhuangdao 066004;China Oil&Gas Pipeline Network Corporation,Beijing 100101)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2023年第16期182-191,共10页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(51875115)。
