Effect of Electromagnetic Stirring on Fine Grain Formation and Tensile Property Improvement for Fe-Ni Supperalloy

摘要

Due to its excellent creep rupture strength and low cost,superalloy GH2984 has becoming a promising material to be used as heat exchanger in the prospective 700°C fossil power plant.The mechanical strength,which is a particularly important indicator for the superalloy,strongly depends on the grain size and crabide distribution.In current study,we have investigated the influence of a rotating magnetic field(RMF)on the solidified microstructures and tensile properties of superalloy GH2984.RMF has been applied to provide a forced convection within the solidifying melt.The melt stirring by a sufficiently high magnetic field provides homogeneous grain size and elements distribution in the sample volume.Meanwhile,yield strength is found to be effectively enhanced for the sample solidified under magnetic field.The result has demonstrated that the RMF method on the melt solidification process shows a promising perspective for refining the grains and promoting the mechanical strength of superalloy GH2984.