High Resolution Transmission Electron Microscopy (HRTEM) and molecular simulation techniques were applied to analyze phase formation in the post-discharge microwave nitriding process of a 4140 steel

Abstract

High Resolution Transmission Electron Microscopy (HRTEM) and molecular simulation techniques were applied to analyze phase formation in the post-discharge microwave nitriding process of a 4140 steel. The results showed the formation of σ-Fe2-3N and γ'-Fe4N. The morphology of the γ'-Fe4N phase was composed by cubic nanoparticles that grows in the 0 0 1 axis direction. Otherwise, the σ-Fe2-3N crystal is associated to hexagonal faces in the [0 0 1] direction which grows forming angles of 120. The comparison between experimental and analytical results allowed a better understanding of the phases formed during this nitriding process..