Welding process simulation under varying temperatures and constraints

Materials suffer a complex situation of both high-temperature and constraint during welding process. The paper firstly addresses the mechanical behavior of material under varying temperature and constraints by experiments, for which 16Mnq steel is chosen as the specimen material. The conditions of experiments are set to be 30–1200 °C for varying range of temperature, 5–50 MPa for varying range of stress constraint. As for welded structures with the middle-thickness or thin plates, a new modeling method, called the equivalent inherent bend-moment method based on the original welding position, is proposed. In this method, a new element, called the local equivalent welding element (LEWE), is developed. The simulation based on LEWE has an ability to mainly consider the coupling influences of various conditions: the high-temperature performance of material, the varying constraint condition, and the welding technique parameters. A typical example has been present to show the effect to predict the welding deformations of plate structures.