The Characteristics Heat Treatment of Precipitation Hardening Stainless Steel Investment Castings
(1) It is better heated to 650℃ slowly before the solution treatment, and then heated up quickly. Stainless steel investment castings can also be mounted high temperature furnace.
(2) The solution temperature of stainless steel investment castings is generally I020~1060℃. The holding time and calculation of thickness is per 25mm lh. Solution temperature of stainless steel investment castings should not be too high, otherwise they will overheat the reduction of stainless steel investment castings, which can increase the residual austenite in steel and reduce the casting strength. Complex shape castings, solution temperature can be reduced to 927℃.
(3) In order to elimination of stainless steel investment castings (especially the big thick) and existence of the dendritic inhomogeneity of segregation, the best temperature uniformity in the solution before treatment. Homogenization temperature is from l000~1150℃, and holding time determined according to casting wall thickness.
(4) To improve the mechanical properties of precipitation hardening stainless steel investment castings in the solution treated with 700~810℃. There are two stage of heat treatment, cooled to the C×2h, and then the C×4h, after that the cutting ability of stainless steel investment castings are also significantly improved.