Experimental Research On Additive Forming And Drilling Of TC4 Titanium Alloy

TC4 titanium alloy has become an important strategic material because of its excellent performance and is widely used in aerospace,vehicles and ships,nuclear weapons,medical equipment and other fields.With the continuous development of the machinery industry,the manufacture of high-performance complex parts with integrated materials,structures and functions is an important development direction of the manufacturing process in the future.The additive and subtractive composite processing and manufacturing method can not only additively shape the complex geometric structure of the part through the additive forming process,but also cut through the material reduction process to ensure the accuracy and surface quality of the part.Manufacturing method of high-performance parts required by "integrated control".This paper analyzes and explores the "laser additive-cutting material" composite processing and manufacturing method of TC4 titanium alloy material.First of all,based on the analysis of the principle and characteristics of selective laser melting(SLM)additive forming technology,TC4 titanium alloy powder was increased by using different laser scanning methods,auxiliary powder thickness and other key additive forming parameters Trial production.Then the surface morphology,density,microhardness and other properties of the TC4 titanium alloy sample were tested,and the influence of different process parameters on the performance of the TC4 titanium alloy SLM additive forming sample was analyzed.Taking the compactness and microhardness of the TC4 titanium alloy SLM additive formed specimen as evaluation indexes,the gray correlation analysis method was used to optimize the TC4 titanium alloy for multiple objectives,and the best comprehensive performance of the TC4 titanium alloy was obtained SLM additive forming process parameters.The TC4 titanium alloy specimens prepared by different manufacturing processes were drilled,and the influence of the drilling process parameters on the drilling axial force,drilling chip shape,drilling hole quality,etc.was analyzed.The angle of the cutting process reflects the additive forming quality of the test piece.Then,considering that the TC4 titanium alloy additive shaped part with a complex structure has a strong sensitivity to the axial force of drilling,it will be easily deformed when the force is too large during the subsequent drilling process.Therefore,on the basis of establishing the theoretical model of drilling axial force,a regression model for drilling axial force prediction of TC4 titanium alloy SLM additive formed parts was established,and the orthogonal advantage analysis method was used to drill The axial cutting force is an evaluation index,and the optimal drilling parameter combination of TC4 titanium alloy SLM additive formed parts is optimized.Through the SLM additive forming test research on TC4 titanium alloy materials,it provides a certain reference for establishing the performance database of all-metal additive forming materials,and has made certain contributions to improving and complementing the additive manufacturing standard system.In order to make full use of the respective advantages of the additive manufacturing method,the drilling and processing test of the structural parts after additive forming is provided to provide a certain reference for the manufacturing method of "additive-subtractive" processing composite.