Structural Transformation at Friction Stir Welding of Aluminum Alloy

EN: On example of aluminum alloy AMg6 the questions concerning development processes of structure formation during friction stir welding are considered. From analysis changes in technological parameters of welding process, a qualitatively different nature of the temperature change is determined when approaching conditions of the super plastic deformation. In accordance with determined heating temperatures, effect grain size of solid solution on hardness in micro volumes of the alloy after forming weld joint was analyzed. From analysis dependence of micro hardness on grain size, it is determined that as the temperature increases, contribution to achieving conditions of super plastic flow from the grain boundaries with large angles of disorientation increases, and effect from solid solution state are decreases.