Predict of residual stress behavior in aluminum friction stir welding by Leeb hardness method


The friction stir welding method it is a modern methods for non- welding material using a milling machine and rotary pin, as a result of heat generated due to rotation of the pin, it generates stresses inherent and it is necessary to know the behavior or the value of these stresses. In this research a new method were invented to predict the behavior of the residual stresses . Three models of friction welding samples are designed at different rotating speed ( 1500 rpm , 1000 rpm and 800 rpm) , then drawing a grid on each sample was drawn vertically and horizontally lines with spaces of 10 mm and 5 mm respectively for each line, Leeb hardness were measured in each node .It found that the hardness is low in the line of welding and then increased at 5-mm ,decreasing at 10 mm then another increase at 15 mm, these change in the value of hardness indicate a change of residual stresses value