Effect of boron alloying element and annealing solution heat treatment on microstructure and mechanical properties of manganese steels

Abstract

In this paper, the effect of boron content in chemical composition of steel on improvement of microstructure and mechanical properties of manganese steels was investigated. The microstructure, by optical, SEM and FESEM microscopy, was investigated. In addition, mechanical tests such as tensile test, hardness and impact tests were performed on the samples. Microscopic test results show that the presence of 0.007% of boron consistently prevents formation of carbides in grain boundaries and also reduces the carbide sizes and improve uniform distribution. In presence of boron, annealing solution heat treatment, improve the morphology of carbides and modified it to spherical shape. The manganese steels by addition of boron alloy element and solution heat treatment, have higher hardness, impact energy and tensile strength.