铸造双相不锈钢叶轮开裂分析与改进措施

Failure Analysis on Crack in Impeller Made of Casting Duplex Stainless Steel

通过对开裂叶轮裂纹位置的观察、裂纹附近区域材料的宏观与微观分析、叶轮生产工艺过程及热处理设备的现场调研,确定铸造双相不锈钢叶轮开裂是由叶轮材料自身存在的铸造缺陷和零件热处理热应力两方面因素综合作用造成,叶轮结构上的厚薄不匀是加重热处理应力的重要原因。在此分析基础上给出了防止铸造双相不锈钢叶轮开裂的措施。

By investigating the locations of cracks in impellers made of casting duplex stainless steel, the macrostructure and microstructure of the material around the cracks, the casting process and the heat-treating equipment for the impellers, it can be obtained that the cracking is due to the materials＇ defects by the un-proper casting process and the thermal stress during the heat treatment. And then the methods for avoiding the cracking are given.