Ti3Al/GH4169异种材料激光焊接头的组织及性能  

Microstructures and Properties of Laser Welded Dissimilar Ti_3Al/GH4169 Joints

作　　者：陈冰清 熊华平 孙兵兵 魏振伟 李万青 Chen Bingqing;Xiong Huaping;Sun Bingbing;Wei Zhenwei;Li Wanqing(3D Printing Research and Engineering Technology Center, Beijing Institute of Aeronautical Materials, Beijing 100095, China;Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation, Beijing Institute of Aeronautical Materials Beijing 100095, China)

机构地区：[1]北京航空材料研究院3D打印研究与工程技术中心,北京100095 [2]北京航空材料研究院航空材料检测与评价北京市重点实验室,北京100095

出　　处：《中国激光》2018年第4期159-169,共11页Chinese Journal of Lasers

基　　金：国家自然科学基金(51405456); 中国科协2016-2018年度“青年人才托举工程”(2016QNRC001)

摘　　要：以金属粉末为焊料,研究了Ti_3Al基合金与GH4169高温合金异种材料之间的激光焊接,分析了接头各区域的微观组织,并测试了接头截面不同区域的显微硬度以及接头的室温拉伸强度。研究结果表明,当焊料为单一的Ti-Ni-Nb粉末时,接头的平均室温抗拉强度为129MPa,焊料与两种母材的界面均没有生成反应层,焊缝的成分主要为Ti-Ni-Nb相、Nb-Ti固溶体及析出的Nb,焊缝与母材界面的显微硬度高于焊缝中心及母材的;当焊料为TiNb/Ti-Ni-Nb/Ni-Cu三种粉末的复合焊料时,接头的抗拉强度增大至180 MPa,接头中主要元素的含量随焊料成分的不同沿焊缝逐渐发生变化,Ti_3Al/Ti-Nb界面具有较高的显微硬度,Ti-Nb区和Ti-Ni-Nb区的硬度值高于NiCu区的。With the metal powders as the filler materials,the laser welding between the dissimilar materials of Ti_3Al-based alloy and GH4169 superalloy is carried out.The microstructures at different areas of the joints are analyzed.The micro-hardness in different cross sectional regions of joints and the tensile strength at the room temperature of the joints are tested.The study results indicate that,when the filler material is only the Ti-Ni-Nb powders,the average tensile strength at the room temperature of the joints is 129 MPa.There are no reaction layers generated in both interfaces between the filler material and the two kinds of base materials,and the welds mainly consist of Ti-Ni-Nb phase,Nb-Ti solid solution and precipitated Nb.The micro-hardnesses at the interfaces between welds and base materials are higher than those of the weld center and the base materials.When the filler material is composed of Ti-Nb/Ti-Ni-Nb/Ni-Cu powders,the tensile strength of the joints increases to 180 MPa.The contents of the main elements in the joints vary gradually along the weld line with the composition variation of the filler materials.The Ti_3Al/Ti-Nb interface possesses the relatively high micro-hardness,and the hardnesses in the Ti-Nb and Ti-Ni-Nb regions are higher than that in the Ni-Cu region.

关 键 词：激光技术 激光焊接 微观组织 力学性能 TI3AL基合金 镍基高温合金 

分 类 号：TG442[金属学及工艺—焊接]