不同冷却方式对7系铝合金MIG焊接头组织和力学性能的影响  

Influence of Different Cooling Methods on Microstructure and Mechanical Properties of 7XXX Series Aluminum Alloy MIG Welded Joints

作　　者：石康柠 曹益[1] 梁志敏[1] SHI Kangning, CAO Yi, LIANG Zhimin(School of Material Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, Chin)

机构地区：[1]河北科技大学材料科学与工程学院

出　　处：《热加工工艺》2018年第5期54-57,共4页Hot Working Technology

基　　金：国家自然科学基金资助项目(51205106)

摘　　要：对12 mm厚7系铝合金板材进行MIG焊接,焊接后采用自然冷却与循环水冷却两种冷却方式,分析水冷对焊接接头组织和力学性能的影响。结果表明,与自然冷却相比,水冷使打底、填充、盖面焊道中心等轴晶粒尺寸减小,焊缝边缘处柱状晶尺寸明显变大;焊缝处硬度有所提高,焊缝-侧软化区范围明显减小,焊接接头屈服强度明显下降,抗拉强度有所提高。The 12 mm thick 7XXX series aluminum alloy plates were welded by using metal inert-gas （MIG） welding, and natural cooling and circulating water cooling were applied after welding. The influence of water cooling on the microstructure and mechanical properties of the welded joint was analyzed. The results show that compared with natural cooling, the water cooling makes the grain size at the center of backing, filling, covering beads decrease and makes the columnar grain area size edge of the weld enlarge. The microhardnes of the weld increases and and the range of soften zone decreases obviously. The yield strength of the welded joint decreases obviously, the tensile strength increases.

关 键 词：铝合金 水冷 显微组织 力学性能 

分 类 号：TG444[金属学及工艺—焊接]