摘要
将AlSi12CuMgNi铝合金挤压铸造的活塞顶圈和锻造的活塞裙进行真空电子束焊接,对优化工艺条件下焊接接头的微观组织和力学性能进行了研究。结果表明,接头成形良好,没有明显的热影响区,焊缝狭窄;焊缝区域主要由细小的α-Al相、α+Si共晶体、初晶硅以及Mg2Si等强化相组成;焊缝中心组织为细小的等轴晶和树枝晶;熔合区组织主要为柱状晶。接头强度不低于挤压铸造母材,焊缝硬度高于母材;焊接接头的拉伸断口断面上分布大量撕裂棱和解理面,呈脆性断裂特征。
The squeezing casting piston top ring and forging piston skirt of AlSi12CuMgNi aluminium alloy were connected by vacuum electron beam welding(VEBW).The microstructures and mechanical properties of joint were analyzed under optimum process conditions.The results showed that the profile of joints were fine.There was no obvious heat effected zone on the martix,and the seam was cabined.The weld zone mainly consisted of small α-Al phase,α+Si phases and Mg2Si phases.The crystallizing morphologes in the seam were fine equiaxed grains and dendrites and that in the fusion area are columnar crystals.The test results indicated that the tensile strength of the joints was by no means lower than that of the base mental and the microhardness of weld zone was higher than those of the base metal.The fractographs of the tensile specimens were brittle with large numbers of laniated edges and cleavage planes.
出处
《焊接技术》
北大核心
2011年第11期14-16,20,共4页
Welding Technology
基金
宁波市自然科学基金项目(2010A610156)
关键词
铝合金
真空电子束焊
组织
性能
aluminium alloy,vacuum electron beam welding,microstructure,property
