CAJ | 학술논문

选用2Al2高强铝合金, 采用三相次级整流电阻点焊机和特定的焊接参数预制内裂纹, 然后在2Al2铝合金固溶温度(500℃)下对接头内裂纹进行6 h的高温愈合处理. 采用金相显微镜、扫描电镜和室温力学性能测试等手段分析接头的微观组织形貌、裂纹形态及断口形貌, 研究接头中裂纹的高温愈合行为及愈合行为对接头力学性能的影响. 结果表明, 在高温热量作用下, 接头微观组织整体均匀化,裂纹产生局部愈合, 接头塑性有所改善, 接头断裂方式由解理断裂转变为准解理断裂. 但经过高温愈合处理后, 接头显微硬度和剪切性能均有所下降.
선용2Al2고강려합금, 채용삼상차급정류전조점한궤화특정적한접삼수예제내렬문, 연후재2Al2려합금고용온도(500℃)하대접두내렬문진행6 h적고온유합처리. 채용금상현미경、 소묘전경화실온역학성능측시등수단분석접두적미관조직형모、 렬문형태급단구형모, 연구접두중렬문적고온유합행위급유합행위대접두역학성능적영향. 결과표명, 재고온열량작용하, 접두미관조직정체균균화,렬문산생국부유합, 접두소성유소개선, 접두단렬방식유해리단렬전변위준해리단렬. 단경과고온유합처리후, 접두현미경도화전절성능균유소하강.
In this article, it adopted three-phase secondary rectification resistance spot welding machine and specific welding parameters to prefabricate inner cracks in 2Al2 high-strength aluminum alloy, then the inner cracks in welded joints of 2Al2 were carried out high temperature healing treatment at solution temperature(500℃) for 6 hours. The microstructure, crack morphology, and fracture morphology of welded joints were analyzed by metalloscope, SEM and room temperature mechanical property test, and the high temperature healing behavior and its influence on welded joint mechanical properties were studied. The results indicated that under the effect of high temperature, the microstructure of welded joint homogenized, the partial cracks are healed, the plasticity of welded joints is improved, and the fracture mode of welded joint changes from cleavage fracture to quasi cleavage fracture. But the microhardness and shear property significantly reduce after high temperature healing treatment.