Investigation of the Effect of Additional Zirconium Diboride (ZrB2) in Spherical Graphite Cast Iron on Mechanical Properties

Abstract

Steering gearbox bodies, which are produced from spheroidal graphite cast iron, experience wear and gaps over time since they operate under load. It is important to strengthen steering gearbox bodies to avoid this. In this study, a steering gearbox body was produced from a spheroidal graphite cast iron material with zirconium diboride at varying rates (0%, 0.227%, 0.455%, and 1.364%). Samples of the material were prepared according to established standards for hardness, compressive strength, and wear resistance tests. The mechanical properties of test samples with and without zirconium diboride (hardness, compressive strength, and wear resistance) were compared. Sample C showed the highest hardness measurement of 243 HB after adding 0.455% zirconium diboride. As the rate of addition increased, the values obtained from the hardness measurement test also increased. Sample C had the highest compressive value of 1438 MPa, with a 0.455% addition rate. It was found that the compressive strength values also increased as the addition rate increased. Wear tests were conducted to analyse wear volume, wear rate, and friction coefficients. A scanning electron microscope (SEM) device was utilised to identify wear mechanisms on the worn surfaces of the samples. Per the results of this study, wear volume values were found to increase with the load value.