Abstract: The laser cladding is employed as a remanufacturing method to repair worn or failed impellers which are made of FV520B steel, one kind of maraging stainless steels. The precipitation behavior has a significant effect on the mechanical property of the steel in the heat affected zone and clad layer. By Gleeble tests, effects of aging temperature and time on the yield strength were inspected. Further, relationship between strength and aging temperature at different aging time was formulated. According to XRD and SEM tests, the effect of the amount of precipitate on the yield strength was verified. The change rule of yield strength with aging temperature and the kinetic characteristics of precipitation of FV520B were explained. Results showed that aging treatment has better effect on FV520B steel at the temperature between 400oC and 600oC. Growth and coarsening of the precipitated phase will break the coherent relationship with matrix, as it will cause exsolution of precipitates and reduction in the material strength.
Authors: Gaite Wu, Gang Wang, Shaopeng Wei, Junying Wang, and Yiming Rong
Keywords: FV520B, Precipitation Behavior, Aging, Laser Cladding