Research Of Geometric Characteristics And Shaping Control Of Formed Structure In Laser Remanufacturing Equipment Parts

The remanufacturing engineering technologies have been widely used with great success for the development of resource conservation and environmental protection society. A lot of remanufacturing forming technologies has improved too. Mechanical parts remanufacturing technology with high-energy beam such as laser was widely used and it overcome the shortcoming of other traditional repair technologies.The quick repairing of local damaged equipment parts by laser remanufacturing forming technology has important military significance and applied value to repair and supply engineering of equipment parts. A classify research method about modularization of laser remanufacturing forming equipment parts was introduced. The typical technological process of laser remanufacturing forming was established, and its key elements were been analyzed too. The paper aimed at restoring of geometrical form of damaged parts, represented the laser forming technique of local structure formed at part damage region with expectant shape. As a result, a software and hardware system of laser remanufacturing forming was build, and the forming and deforming mechanics of laser remanufacturing forming structure were been expounded. In addition, the problem of non-uniform geometric character of formed structure in laser remanufacturing forming process was been solved. The practical applications of laser remanufacturing forming damaged surface, thin-wall structure, and local broken three-dimensional structure were been introduced too.The main research conclusions are as follows:With the features such as high flexibility, part repair on site and rapid forming with high dimensional accuracy, the laser remanufacturing forming software and hardware system was been built. The system was the base of application of laser remanufacturing forming technology. The system mainly composed with DLA60100 solid-state laser, AX-V6 robot, and AX-ST off-line programming software. The location accuracy of laser scan path and adaptability of forming path programming were been increased by using this system. Two designs of coaxial powder feeding nozzle with ring-shaped powder deliver passage and four pipes surround laser beam were represented, and the shortages of lateral powder feeding nozzle such as poor powder usage, low formed efficiency and aeolotropism at laser scanning path were overcame.The theoretical basis of applications of damaged parts geometrical shape restores technology was system researched, which composed with geometry research of laser remanufacturing forming line, surface, thin-wall structure and 3D structure. A nonuniform phenomenon of geometrical characters of laser formed local structure was discovered, and its formative reasons were explained by analyzing molten-pool laser energy input, powder particles input and the shape of molten-pool bounded surface shape. The results show that the difference between actual processing parameters and ideal processing parameters was the main reason that leads to nonuniform phenomenon of geometrical characters. A technologic method to avoid this nonuniform phenomenon by quantitative accurate control of processing parameters was been presented.The geometric shape control methods of laser formed structure were been investigated systematically. The dimensional accuracy of laser formed structure was notable increased by using these methods. The function between mainly processing parameters, such as laser power, laser scanning speed and powder feeding rate, and laser formed structure geometry was been built. A dimensional prediction model was been built based on energy conservation principle and equation of mass conservation of laser molten-pool. The model forecast accuracy was satisfied and with maximal 5% error by experimental verification. According to the model, the geometric shape control objects were follows: laser-scanning speed, powder feeding rate and molten-pool bondage surface shape.Using laser remanufacturing forming technology, a wear part surface with complex shape, a thin-wall structure with top notch and a part with local structure cracked were been repaired creatively. The successful repairing result of these equipment parts indicated that we have expanded the application range of laser remanufacturing forming technology. The typical part of surface damaged with complex shape was a camshaft of tank engine, and its worn cam face was shape restored. The typical laser remanufacturing forming thin-wall part was a thin-wall cylinder with a top notch, and typical local 3D structure cracked parts were a low-load spur gear with broken gear tooth and a strutting piece of airplane undercarriage with cracking ribbed panel. The reparative structures with prospective shape and high dimensional accuracy were laser formed, and the key technological operation of shape control of laser formed structure was been presented too. The researches of laser remanufacturing forming typical parts have important reference significance to remanufacturing other parts with similar shape or similar damage.