Analysis of coupled temperature, stress, and strain fields during rotation friction welding of LY12 aluminum round bars

To understand better the process of friction welding, it is essential to calculate the variations of temperature, stress, and strain fields of welding interface material during the almost instantaneously completed friction welding process. As Chinese aluminum alloy LY12 is a commonly used aerospace material, we calculated such fields for continuously driven friction welding of LY12 alloy round bars. In the full paper we explain and discuss in much detail our FEM (finite element method) calculation and the calculated results. We established the coupled thermal-mechanical FEM model. The thermal-mechanical behavior of welding interface material was numerically simulated by using MSC Corporation commercial FEM software. For our numerical example, FEM result shows that 520°C, the lower limit of LY12 fusion point, is reached at the end of 0.35 s of rotation friction welding. During the entire process of rotation friction welding, the calculated equivalent strains all increase monotonically; the equivalent strain at the center of circular section of interface material is the largest.