Analysis on Crack Reason for ZG1Cr18Ni9Ti Stainless Steel Casting
The cracks detected in the production process of ZG1Cr18Ni9 Ti casting were investigated.Using metallographic examination method,the Ti N phase gathered in the grain boundary matrix was found.By comparing the microstructure with the raw material used for remelting,it can be obtained that the gathered Ti N generates during the solidification process of the casting.Because of the slow solidifying rate in some part of the casting,Ti N phase has enough time to be pushed into the grain boundary,and finally becomes to be the crack source,which can spread under hot and cold mechanical stress.