Research On Building Process Of Thin-wall Parts Base On Laser Deposition

The British Economist magazine believes that additional material manufacturing technology and other digital technology will promote the third industrial revolution.The additive manufacturing technology of full dense metal parts can be manufactured by laser cladding forming.Compact structured and fine-performance thin-walled parts can be obtained by laser cladding forming.The laser cladding 3D printing and remanufacturing system was used to study the forming process of the cladding.Water cold worktable was used to carry out experiments.Single cladding is the basis of the forming of thin-walled parts.The height and width of the single track cladding and the depth of the molten pool are mainly determined by the laser cladding parameters such as laser power,powder feeding rate and scanning speed.The relationship between the geometry of single track and the laser power,powder feeding rate and scanning speed in the laser cladding process was obtained.The influence of process parameters on the width and height of cladding layer was analyzed by orthogonal experiment,and the regression equation was established.In this paper,the thin-walled parts are made by laser cladding single channel multilayer forming.The thin wall parts formed by laser cladding are formed by stacking of single track cladding layer by layer.The selection of process parameters and reasonable path,control in the process of forming the Z axis by the lift height,forming straight and curved thin-walled parts,solves the forming of sticky powder,collapse,high starting point,tail shrinkage and crack phenomenon,gets good surface of thin-walled parts.Study the effect of acceleration on the forming and changing the acceleration to get the better forming quality.The curvature of the thin-walled parts with different curvature is studied.The height of the curvature is small and the curvature is large.The experiment of the surface quality of forming thin-wall parts and the variance analysis shows the powder feeding rate has the greatest influence on the surface quality.The microstructure of the formed thin-walled parts is good,and the tensile strength of the thin-wall specimen formed by laser cladding is 573.7MPa,which is superior to the tensile strength of the hot-rolled stainless steel plate.The relationship between the substrate temperature and the process parameters was studied by experiments of single pass cladding temperature.The temperature changes in the forming process of thin wall parts were measured by two methods: thermocouple and thermal imager,and low temperature of thermal imager by the temperature curve was fitted.In the process of metal forming,it was a complex process of multi field coupling.The combination of the numerical simulation of the temperature field and the temperature field experiment can be used to study the changing process of the temperature field more directly and comprehensively.By using the method of numerical simulation of temperature field on the temperature field of laser cladding forming and thin-walled process were simulated and compared with the experimental results,the fitting data accord with the same simulation parameters of thin-wall parts are simulated on forming temperature accumulation and variation.