Research On The Stabilization Treatment Technology Of Laser Additive Manufacturing Parts

In order to solve the problem of residual stress and dimension instability in laser material manufacturing,two kinds of stabilized post-treatment techniques,heat treatment and vibration stress relief,were studied in order to reduce the manufacturing residual stress of AlSi10 Mg and TC4 base parts,and increase the stability of the laser-produced parts.First of all,the generation and distribution of residual stresses were studied by means of FEM simulation and experiment.The selection of heat source model,the boundary conditions,the application of the function of "birth-death element method" in the numerical simulation of temperature field and stress field of laser additive manufacturing are introduced.After the temperature field was obtained,the residual stress field was obtained by indirect coupling method.Residual stress was measured by X-ray diffraction method,and the distribution of residual stress was determined by comparison of numerical simulation results.The influence of heat treatment on the residual stress of AlSi10 Mg sample produced by laser additive manufacturing and the effect of heat treatment on the microstructure and phase of the material were studied.And the heat treatment applied to a typical part-TC4 base.The residual stress reduction rate was up to 56.6%.The mechanism of vibration stress relief of parts made by laser material is expounded from both macroscopic and microscopic aspects.The vibration stress relief process parameters such as excitation frequency,excitation point,support mode and excitation force are selected by means of FEM simulation and modal test.The VSR test system of AlSi10 Mg sample and TC4 base was established,and the aging effect of the selected process parameters was verified by the VSR test,and the spectrum harmonics aging of the base with complex structure was carried out.The effect of stress relief on the aging and aging of the heat treatment was compared and evaluated by the residual stress measurement.The effects of different post-treatment methods on the dimensional stability were compared by means of static method.This paper systematically studies the stabilized post-processing technology of laser additive manufacturing parts,which fills up the gap of application of VSR technology in laser additive manufacturing.And the effect of the stabilization technology on the dimensional stability of the laser material was studied.Forming a set of laser materials by the stability of manufacturing parts of the vibration aging method,to further promote the technology of material is of great significance.