Research On Crack Repair Of TC4 Casing By Laser Clading

In order to meet the urgent requirement of industrialized application of the application of the TC4 titanium alloy plate with crack repair method. The welding repair of TC4 titanium alloy casing is realized by laser cladding. By means of metallographic analysis, scanning electron microscopy, energy spectrum analysis and intensity analysis, the microstructure, tensile strength and fracture characteristics of TC4 titanium alloy were studied by means of different parameter s(laser power, scanning speed, wire feeding speed).In this paper, the experimental study on the 2mm thick TC4 alloy was carried out in the experimental materials. In the process of single wire welding, the increase of the laser power, the depth and width of the laser beam, and the width of the weld, and the width of the welding process and the width of the wire are decreased. The laser power is 1.3k W, the laser scanning speed is 0.6m/min, the wire feeding speed is 1.2m/min, and the process parameters are repaired, and can be obtained without the welding defects and the optimum penetration depth.The contents of Fe, Ti, Si, V and Al were not changed significantly from the central position of base metal to weld metal, and the joint region was α-Ti and β-Ti two phases. The gray sphere of the parent material of the original TC4 is gradually becoming a long block, and a large number of beta phase is generated at the boundary. At the same time, the Al and V elements are distributed in the lamellae, resulting in the enrichment of Al elements to the α-Ti phases, and the V element to the β-Ti phases.With the increase of laser power, scanning speed and wire feeding speed increase, the tensile strength of the joints at room temperature increases at fir st and then decreases. When the laser power is 1.3k W, the laser scanning speed is 0.6m/min and the wire feeding speed is 1.2m/min, the tensile strength of the welded joint of TC4 titanium alloy is the highest, 1056 MPa. Several parameters of high temperature tensile strength were selected, and the tensile strength of the joints was 1.2m/min when the laser power was 1.2k W and the laser scanning speed was 0.6m/min, the tensile strength of the joints was the highest at high temperature(400℃), and reached 627 MPa.Laser power is 2.3kW, the laser scanning speed is 0.6m/min, the wire feeding speed is 1.2m/min, and the process parameters are repaired, and can be obtained without welding defects and the optimum penetration depth. TC4 titanium all oy casing supporting plate crack laser cladding repair after 300 hours of ground testing, the results of the TC4 titanium alloy casing laser cladding repair department has not produced a crack, to assess the performance of the index.