Surface Nanocrystallization of 3Cr13 Stainless Steel Induced by High‐Current Pulsed Electron Beam Irradiation

Abstract

The nanocrystalline surface was produced on 3Cr13 martensite stainless steel surface using high-current pulsed electron beam (HCPEB) technique. The structures of the nanocrystallized surface were characterized by X-ray diffraction and electron microscopy. Two nanostructures consisting of fine austenite grains (50–150 nm) and very fine carbides precipitates are formed in melted surface layer after multiple bombardments via dissolution of carbides and crater eruption. It is demonstrated that the dissolution of the carbides and the formation of the supersaturated Fe (C) solid solution play a determining role on the microstructure evolution. Additionally, the formation of fine austenite structure is closely related to the thermal stresses induced by the HCPEB irradiation. The effects of both high carbon content and high value of stresses increase the stability of the austenite, which leads to the complete suppression of martensitic transformation.

Thermal Cycling Behavior of Thermal Barrier Coatings with MCrAlY Bond Coat Irradiated by High-Current Pulsed Electron Beam

“…Moreover, very fine precipitates of less than 10 nm were located at the grain boundaries and in particular most often at triple junctions. Similar results were previously reported in 3Cr13 steel and D2 steel irradiated by HCPEB irradiation. The existence of these granular precipitates can suppress the expansion of grain boundaries, which has a positive effect on the high temperature oxidation resistance of TBCs by a grain size constraining effect.…”