铝合金焊接凝固裂纹高温动态开裂行为

Dynamic cracking behaviors of weld solidification cracks for aluminum alloys at elevated temperature

摘要: 详细研究了5083、6082、ZL101三种铝合金的凝固金相组织,观察和记录了三种材料高温拉伸开裂动态过程及开裂后的断口特征。结果表明,材料的冶金因素制约着凝固裂纹的动态开裂行为,即材料的冶金特性不同,它们的凝固裂纹开裂模型也不同。文中由此总结了凝固裂纹的三种开裂模型。第一,裂纹形成时存在"愈合作用",ZL101属于此列。第二,裂纹形成时伴随着金属桥的变形与断裂,如5083材料。第三,裂纹形成时晶粒是沿液膜分离,如6082。

Abstract: The solidification microstructures of three Aluminum alloys of 5083,6082 and ZL101 were investigated and their dynamic cracking behaviors and the fracture features at elevated temperatures were observed and recorded.The results show that the metallurgical factors play a main role on the dynamic cracking behaviors of weld solidification cracks,that is to say,the dynamic cracking models of different alloys are different with their metallurgical characteristics.Therefore the dynamic cracking models can be classified into three types,one with healing effect such as ZL101,one with deformation and breaking down of metal bridge,like 5083 and another with the separation of liquid film along grain boundary such as 6082.