Abstract: The welding method, process technology and base principles of friction stir welding(FSW) are presented. By means of a large variety of FSW on LF6 has gotten same tensile strength with base metal. Joint strength of LY 12 by 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 has 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.

Key words: Aluminium alloy, Friction stir welding