铝合金搅拌摩擦焊技术研究

论述了搅拌摩擦焊的焊接方法、工艺过程和基本原理；通过大量的工艺参数优化，解决了焊缝中的孔洞问题，使ＬＦ６板材搅拌摩擦焊的焊缝达到与母材等强，ＬＹ１２焊后未经热处理，连接强度接近母材的８０（。由金相分析可以看出，搅拌摩擦焊属于固相连接，焊缝晶粒细小，无气孔、夹杂、裂纹等焊接缺陷。初步应力测试发现，搅拌摩擦焊焊缝比熔焊焊缝的残余应力低。试验研究结果表明，搅拌摩擦焊焊接过程稳定可靠，焊接接头性能良好，具有广泛的应用前景。

ALUMINIUM ALLOYS FRICTION STIR WELDING TECHNOLOGY

The welding method, process technology and base principles of friction stir welding(FSW) are presented. By means of a large variety of parameter optimization of technology, the welding interface of FSW on LF6 has gotten same tensile strength with base metal. Joint strength of LY12 by FSW, non-heat-treated after welding, has reached 80% of base metal. From metallograph, it is proved that friction stir welding is a kind of solid phase joint, and with fine weld particles there is no welding defeat such as gas hole, inclusion and crack etc. By stress tests, the residual stress of FSW is lower than general fusion welding. A series of experiments and research results have demonstrated that friction stir welding is a stable process with high repeatability, excellent joint and great potential application.