热处理对TC4-DT/TC21钛合金线性摩擦焊接头组织和性能的影响  

Effect of Heat Treatment on Microstructure and Properties of TC4-DT/TC21 Titanium Alloy Linear Friction Welded Joints

作　　者：高潘 曾卫东[1,2] 张传臣 徐建伟 Gao Pan;Zeng Weidong;Zhang Chuanchen;Xu Jianwei(Defense Technologies Innovation Center of Precision Forging and Ring Rolling,Northwestern Polytechnical University,Xi'an 710072,China;Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment,Northwestern Polytechnical University,Xi'an 710072,China;Aviation Technology Key Laboratory of Aviation Welding and Joining Technology,AVIC Manufacturing Technology Institute,Beijing 100024,China)

机构地区：[1]西北工业大学国防科技工业精密锻造与环轧技术创新中心,陕西西安710072 [2]西北工业大学陕西省高性能精确成形技术与装备重点实验室,陕西西安710072 [3]中国航空制造技术研究院航空焊接与连接技术航空科技重点实验室,北京100024

出　　处：《航空科学技术》2021年第9期50-56,共7页Aeronautical Science & Technology

基　　金：航空科学基金(201911053001)。

摘　　要：为进一步提升TC4-DT/TC21线性摩擦焊接头的综合力学性能,对比分析了焊接接头一次退火和双重退火对微观组织和力学性能的影响。结果表明,一次退火后,接头各个区域的组织特征与退火前差异较小,焊缝中心区为细小的再结晶晶粒及针状α相,热力影响区呈现沿振荡方向拉长的流线组织。但双重退火后,接头组织发生明显变化,焊缝中心区出现晶粒长大、片层α相粗化以及晶界α相不连续等现象。热力影响区内α相片层粗化且片层间距增加,同时在粗化的片层α相周围析出许多长大的短棒状α相。母材区内片层α相发生粗化且有次生相析出。性能对比显示双重退火明显优于一次退火,其中强度和冲击功分别提升了91MPa和24.4J,塑性仍保持较高水平。In order to further improve the comprehensive mechanical properties of TC4-DT/TC21 linear friction welded joints,the effects of simple annealing and duplex annealing on the microstructure and mechanical properties of welded joints were compared and analyzed.The results show that after simple annealing,the microstructure characteristics of each zone are less different from those before annealing.Namely the weld center zone is composed of fine recrystallized grains and needle-likeαphases,and the thermo-mechanical affected zone presents a streamlined structure elongated in the direction of oscillation.However,after the duplex annealing,the joint structure changes significantly,and weld center zone appears grain growth,lamellarαphase coarsening,and grain boundaryαphase discontinuity.In the thermo-mechanical affected zone,theαlayer is coarsened and the interlaminar spacing increases.At the same time,many long and short rod-likeαphases are precipitated around the coarsened lamellar alpha phase.In the base material zone,the lamellarαphase is coarsened and secondary phases are precipitated.Comparison of mechanical properties shows that duplex annealing is significantly better than simple annealing,in which the strength and impact energy are increased by 91MPa and 24.4J respectively,the plasticity remains at a relatively high level.

关 键 词：线性摩擦焊 焊后热处理 钛合金 双重退火 力学性能 

分 类 号：TG166.5[金属学及工艺—热处理]