Ni-Cr高温合金薄壁件消失模铸造研究进展OA

Ni-Cr superalloy thin-walled castings are commonly used in high-temperature load-bearing structures,and their forming quality is jointly limited by the integrity of mold filling,solidification feeding,and dimensional stability.Lost foam casting(LFC)has the characteristics of near net shape without sand cores or parting surfaces,which is suitable for the manufacture of complex structural castings.This paper summarizes the quality issues of LFC thin-walled high-temperature alloy castings,the foam patterns and their pyrolysis behavior,the lost foam coating systems,the pouring parameters,the negative pressure and the vibration compaction,the numerical simulation,and the parameter optimization methods.The research shows that the foam patterns and the coating systems are key factors affecting the LFC forming quality.Foam decomposition and gas release can cause changes in the front of the molten metal,increasing the difficulty of quality control in thin-walled areas.Future research should strengthen the accumulation of foam pyrolysis parameters,coating properties,interfacial heat transfer and verification data for typical thin-walled parts,and adopt the route of combining simulation and experiment to promote the development of casting process in the direction of digitization and precision forming.