| In aerospace industry, weight of structure is very important; entirety structure does well to reducethe weight, so some new structures come out fast. Porous structure is one of new light structures, andit is widely used in aerospace industry. Because of its specific structure and physical property, it isdifficulty to weld with common technique. Diffusion bonding is a research hotspot in aerospaceindustry, and it has plenty of advantages. So by this way, it can get the porous structure well.In this paper, Diffusion bonding of complex porous structure has been researched as follows:(1) According to relevant theories, the behavior of metal atom diffusion has been detailedanalyzed, and the diffusion phenomenon of Ni and Cr in0Cr18Ni9have been found out. By plenty ofexperiments, influences of different parameters (temperature, pressure and time) to diffusion bondinghave been investigated. Find out optimized parameters with well diffusion bonding quality.(2) Due to the specific structure of porous structure, with the help of ABAQUS, it has beenanalyzed the pressure affected by different parameters of structure. The right pressure has beencalculated. Two different plans have been designed, one is forced by gas pressure, and the other is byrigid die.(3) Two experiments have been completed, the sizes of porous structure have been measured,and according to microstructure of bonding interface, proper plan has been got.Through the above work, draw the following conclusions:(1) The optimal parameters of diffusion bonding are as follow: the bonding temperature is930℃, pressure is6MPa and time is40minutes.(2) During the plan forced by gas pressure, the pressure is5.6MPa, temperature is930℃，andtime is40minutes, the interface contact well, and the whole interface has been well welded.(3) In the plan forced by rigid mould, the force is9kN, it has been successful to get the model.But because of the asymmetry the pressure, a little aperture has been found. |
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