| Magnesium alloy is one of the lightest of those alloys used as the basis of constructional materials. Its density is small and excellent in electromagnetic shielding, thermal conductivity, and easy recovery. Magnesium is widely used in the fields of aerospace, automotive, communication and electronic industry. Superplastic forming/diffusion bonding is a combination technology developed on good solid-state bonding performance of superplastic material. It can not only superplastic forming but also diffusion bonding at the same time to produce high performance integer part with complicated shape part. Implementation of the technology reduces the overall weight of the parts, makes integral parts of thin-walled complicated parts, shorten the integrative manufacturing cycle, improved the overall performance.With finite element software MSC.MARC, the SPF/DB process of ZK60 magnesium alloy corrugated part was simulated by three-dimensional finite element model in this paper. Penalty function method based on rigid/visco plastic finite element method was applied to obtain the forming law and thickness distribution law at different forming stages of corrugated part. The location of risky point during the forming process of corrugated part was predicted. Using orthogonal test method, the corrugated part forming parameters of temperature, strain rate and the friction coefficient were optimized, the optimized pressure curve was obtained.Developed N11 gasification agent, combined the optimized pressure curve obtained from the numerical simulation, the SPF/DB experiment of ZK60 magnesium alloy corrugated part was carried out successfully and the thickness distribution law were compared with the results from the SPF/DB simulation, finding these two kinds of results in good agreement with each other. The causes of error were analyzed, which provided theoretical basis on control the forming quality of corrugated part and predict forming defects.The corrugated part microstructures of different areas blank hold, side, bottom, and corner were observed respectively to get the relationship of grain size and strain. The cavity size and cavity volume fraction of different areas were observed and calculated in order to obtain the relationship of cavity size, cavity volume fraction and strain. TEM photographs of corrugated part were analyzed to study the mechanism of superplastic forming. The micro-morphology of diffusion bonding part was observed, the results showed that the diffusion bonding was very good.
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