INFLUENCE OF THE QUANTITY OF THE FEED OF A WORKING TOOL IN FRICTION STIR WELDING ON THE MECHANICAL PROPERTIES OF JOIN COMPOUNDS OF ALLOY 1565 h
In this article the results of application of friction stir welding technology for joining rolled plates of non-heat-treatable alloy Al-Mn are showed. The welding process was implemented using several technological modes. Features, which taking into account, when choosing technological parameters, for optimal properties were identified by analyzing the samples of the weld corresponding to the modes. Researching of the structure of the weld core revealed a special layered metal structure, which consists of recrystallized grains separated by high-angle boundaries. The independence of this structure from the initial state and thickness of the sheets being welded indicates the self-organization of the microstructure of the core zone, the formation of which is determined by temperature and plastic deformation. It was experimentally established that when temperature and time parameters are violated, defects in the form of discontinuities are localized at the boundary of the weld and the base metal, the formation of which is caused by the incompatibility of the deformation of the weld metal and the adjacent base material. It is shown that the fracture mechanism of a welded joint is determined by the presence of defects that reduce the effective cross section of the welded joint.