Investigating the effect of titanium addition on the wear resistance of Hadfield steel

¹ Department of Materials Science and Engneering, NajafAbad Branch, Islamic Azad University, Isfahan, Iran
² Department of Mechanical Engineering, Tiran Branch, Islamic Azad University, Isfahan, Iran
e-mail: kamran_amini1978@hotmail.com

Received: 31 July 2014
Accepted: 19 November 2014

Abstract

In this study, the effect of titanium addition on the microstructure and wear behavior of Hadfield steel was investigated. To do so, four groups of samples with different titanium contents of 0, 0.2, 0.4 and 0.6 wt% were prepared. After casting, the samples were austenitized at 1100 °C for 3 h and quenched in water subsequently for solution treatment. The microstructure of the samples was investigated using an optical microscope (OM) and scanning electron microscope (SEM). For more studies the carbide composition was analyzed via energy-dispersive spectroscopy (EDX). A wear test was performed via a pin-on-disk wear testing machine. The results show that after heat treatment the microstructure of the titanium-free sample is fully austenitic, while the other samples show an austenitic structure with non-continuous carbide precipitates. It was also revealed that titanium addition improves the hardness and wear resistance of the samples. The highest wear resistance was observed in the sample with 0.6 wt% titanium content. It was also shown that the predominant wear mechanisms are adhesive and tribo-chemical. Beyond this, the effect of cold working via a hammering treatment was studied on the samples and revealed that austenite-to-martensite transformation improves the hardness and wear resistance significantly.