Microstructure and properties of Ni-based superalloy sheet prepared by EB-PVD

Large-scale Ni-based superalloy sheet was prepared by electron bean physical vapour deposition. Micro structures and micropores of as-depoited and heat treated superalloy sheets were studied by scanning electron micro scope, atomic force microscope, and optical microscope, The results show that the as deposited superalloy sheet is mainly composed of columnar grain. whose major axes are parallel to the normal line of the sheet, The average diameter of crystalline grain., in minor axis direction is about 300 nm, After beat treatment. flu, superalloy sheet consists of equiaxed grains, the nanopores with high interfacial energy gather and form fewer pores with larger size. And there is notable increase in toughness.