The Effect of Titanium Addition on the Microstructure and Wear Resistance of High Chromium Cast Iron

High-chromium cast iron (HCCI) is widely used in the mining and metallurgical industries due to its excellent wear resistance. However, its coarse eutectic carbides often result in insufficient toughness, leading to premature failure. To improve its overall performance, this study systematically investigated the effects of different Ti addition on the microstructure and mechanical properties of HCCI containing 16 wt.% Cr and 2.8 wt.% C.X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were employed to characterize the phases and microstructure, while hardness testing, compressive testing, and friction and wear experiments were conducted to evaluate the mechanical and wear-resistant properties. The results indicate that the addition of Ti promotes the transformation of carbides from network M₃C to fine lamellar M₇C₃, while the concurrently formed fine TiC particles refine the eutectic carbides and improve their distribution. The compressive strength of the HCCI first increases and then decreases with increasing Ti content, reaching a peak at 1.6 wt.% Ti. Analysis of the wear mechanism revealed that specimens with a proper Ti content exhibited a plowing grooves wear morphology, with abrasive wear being the predominant mechanism. In contrast, specimens with excessive Ti (≥1.6 wt.%) exhibited a decline in wear resistance due to a brittle spalling mechanism induced by the coarsening and agglomeration of TiC. Considering the microstructure, mechanical properties, and wear resistance comprehensively, the optimal Ti addition level for HCCI in this study is 1.2 wt.%.