高纯铝硅钎料的高温力学性能和显微组织特征  

High Temperature Mechanical Property and Microstructure Characteristic of High Purity Al-Si Filler Metal

作　　者：史平安[1] 何建军[2] 王军[1] 李盛和[2] 

机构地区：[1]中国工程物理研究院总体工程研究所,四川绵阳621900 [2]表面物理与化学国家重点实验室,四川绵阳621907

出　　处：《热加工工艺》2011年第23期133-136,共4页Hot Working Technology

基　　金：国防预先研究基金资助项目(426030403);中国工程物理研究院重大基金资助项目(2005Z0302)

摘　　要：为了降低铍焊缝的缺陷,提高焊接接头的强度,本文针对所研制的高纯铝硅钎料,采用高温拉伸试验、SEM扫描、能谱分析等分析手段,分析研究了其高温力学性能、组织特征和钎焊接头的成分分布,探讨了焊接缺陷形成机制。结果表明,冷却速率通过改变初生α-Al相和共晶β-Si相的形态进而影响到材料的力学性能,冷却速率增加,共晶β-Si相变细,相间距减小,材料的热塑性提高。焊缝部位的SEM及能谱分析结果显示,裂纹部位的C、O、Ca等杂质元素含量偏高,尤其是BeO在晶界的偏析严重,这些脆性相在晶界处聚集,导致局部区域塑性降低。In order to improve the welding quality and decrease the defects in laser welding-brazing of beryllium. The mechanical properties of high purity Al-Si filler metal were evaluated by high-temperature tension experiment. The microstructure characteristic, component distribution and interfacial reaction of the welded joints were analyzed by SEM and EDS. The mechanism of welding crack was investigated in the process of laser welding-brazing of beryllium. The results show that the grain size of β-Si dendrite becomes finer and uniform, with the increase of cooling rate, and all of those can make the tension strength, thermal plasticity improve. High content of C, O and Ca is detected in the crack band gathering at crystal boundary. Especially, BeO exists in the micro-cracks, the brittle phase segregates and aggregates in the grain boundary, which can result in the decrease of plasticity in local area.

关 键 词：铝硅钎料 高温力学性能 显微组织 焊接缺陷 

分 类 号：TG425[金属学及工艺—焊接]