A novel finite element method for simulating residual stress of TC4 alloy produced by laser additive manufacturing

With the continuous increase in the demand for the aerospace industry, laser additive manufacturing (LAM) has become an effective means to prepare aerospace materials. However, the process of LAM has a fast heating and cooling process, which produces a large residual stress in the structure, resulting in the mechanical properties of the effects of residual stress, leading to problems such as buckling and fracture of the structure. With the advantages of dynamically displaying three-dimensional stress, finite element analysis has become an important way of studying LAM. The simulation of LAM of Ti-6Al-4V (TC4) alloy is established. However, the traditional main simulation method "Model Change (an interaction of ABAQUS)" may have the problem of the distribution of residual stress "fish-scale-shape", which would make great obstacles to the next study. In order to solve the problem of the distribution of "fish-scale-shape", a new method of progressive activation element (PAE) is proposed. The correctness of the two methods is verified by comparing the results obtained by the two methods with experimental results. Two main parameters of the laser power and the number of cladding layers in the LAM process are studied in this paper: with the increase of laser power, the residual stress increases simultaneously; with the increase of the number of cladding layers, the residual stress does not change much and decreases slightly. The study of this paper gives a new solution to the study of LAM and similar topics, and provides guiding significance to control and reasonable suppression of the structural residual stress of LAM.