Microstructure, hardness, and wear resistance of high-carbon hypereutectic high chromium irons containing W for use as roller sleeves

Abstract

High chromium irons (HCI) have rarely been investigated the impact of varying W content on the microstructure and performance of high-carbon irons by scholars. In this study, after calculating by Java-based Materials Properties software (JMatPro), the casting alloying method was applied to explore the effect of adding W (0-15 wt%), Mo 3 wt%, and C 6 wt% on HCI to prepare highly wear-resistant and hard materials. The results showed that the maximum volume fraction of carbide was 38% at C 6 wt%. The addition of W promoted the formation of M6C with a maximum volume fraction of 21%, which increased the hardness to 64.5 HRC and reduced the weight loss to 0.062 g. Since W10 (the iron with W 10 wt%) and W15 (the iron with W 15 wt%) exhibited similar wear resistance but lower impact resistance, the W10 samples were heat-treated. W10 after QT550 (quench and temper heat treatment at 550 °C) sample developed a large number of M6C-type carbides and martensite in the matrix, which improved the properties of the matrix by diffusion strengthening, leading to a hardness of 70.0 HRC and a reduction in weight loss to 0.035 g. Compared to the Cr20 reference iron, W10 after QT550 was 22.8% higher in hardness and 76.8% lower in abrasion. Concurrently, an experiment was conducted on the production of roller sleeves. With the use of W10 after QT550, the lifetime of the roller sleeve was increased by 1.6 times.

Keywords

• High-chromium cast iron
• Wear-resistant material
• High hardness materials
• Roller sleeves