Microstructure and properties of hypereutectic high chromium cast iron containing nitrogen

Abstract

This article investigates the effect of N content on the microstructure, mechanical properties and wear resistance of hypereutectic high chromium cast iron (HHCCI). With the increase of N content, the primary carbides are obviously refined, the austenite content increases, and the dispersed granular Cr2N precipitates. After quenching at 1000 °C, secondary carbides are precipitated from the matrix, the matrix transforms into martensite + retained austenite. With the increase of N content, the corrosion resistance of HHCCI increases, and 0.3 wt.% N HHCCI shows the best corrosion resistance. With the increase of N content, the wear resistance of HHCCI increases. The wear resistance of HHCCI with 0.15 wt.% N is the best, which is 1.57 times that of HHCCI without N.