Special Casting Repair Technology Research And Application

Our country casting industry is seriously restricted by the two bottlenecks--low eligible rate of casting and low repair rate of casting defects. As an important way of sustainable development strategy, remanufacture is more and more valued by people.50% cost,60% energy and 70% material of a new one will be saved by remanufacturing the damaged or scrapped casings to meet or exceed performance of new products, in which special repair technology will be used. It not only provides a new mean for enterprises to improve efficiency and low energy consumption but also meets the strategic objective of constructing national circular-economy, building a conservation-oriented society and developing an innovative country.From the start of machine tool castings and vehicle casings, the research background, the research significance of this paper, and the status of remanufacture technology developing at home and abroad are introduced in this paper firstly. Also, the related typical castings'wears and current special repair technologies are presented, the advantages and disadvantages of special technologies and traditional methods are compared and an unprecedented repair instance of shield's drive shell by the special technologies is suggested. Basing on the Beijing Aoyukexin Surface Engineering Co., Ltd, this paper mainly theoretically analysis and studies the repair and its results of Aoyukexin's room-temperature cold fusion technology, and improves the traditional adhesive technology for the problem at practical applications and innovatively composites the adhesive technology and new type of thread technology to a new technology. After the study of theory of room-temperature cold fusion technology, a repair example of this technique is recommended. Through the macro-test, the base metal was always kept at room temperature, and no welding marks or cracks after repair. Under the metallurgical microscope, metallographic analysis represents the microstructure of base metal having slightly changes and having small number of cementite in transition zone. Spectroscopy analysis displays markedly elements diffusion, which says that the fill material is a metallurgical bonding with the base material, combined with high bonding strength. Then, the repair results of the different fill materials:low carbon, wire and iron filings of the same material with the base material are compared to analysis the influence to repair results. Finally, for the lack of casting defects repair in adhesive technology, a new technology compositing adhesive technology and new type of thread is proposed and its feasibility is verified by experiment.