Temperature/stress field numerical simulation of hollow blade produced by laser rapid forming

A transient temperature/stress field finite-element model for the laser rapid forming (LRF) process of a hollow blade of aeroengine is developed. The deposition process is simulated with the finite element birth and death technology, the thermo-plastics is analyzed by bilinear isotropic hardening and Von Mises yield criteria, and the indirectly coupled temperature/stress field evolution during the LRF process of a TC4 alloy hollow blade is simulated. The results show that during the LRF process of a TC4 alloy hollow blade, the temperature/stress field in the TC4 alloy hollow blade is dynamically developed with the movement of melting pool and increase of forming height. For the reason of cooling/constrain effect of the substrate and heating/stress-release effect of the melting pool, the temperature/stress field gradient distributes along the altitude direction. The temperature declines from the top to the bottom, and the heat dispersing direction was from the top to the bottom i.e., from the melting pool to the substrate. The stress field increases from the top to the bottom, and reaches a maximum at the bottom of the blade. When the blade was cooled to room temperature, the residual stress distribution is similar to that in the cladding process, expect for a larger stress at the top of the blade.