How can the wear resistance of high-chromium products be improved?

High-chromium cast iron is the third generation of wear-resistant materials developed after ordinary white cast iron and nickel-hard cast iron. Due to its unique structure, high-chromium cast iron possesses significantly higher toughness, high-temperature strength, heat resistance, and wear resistance compared to ordinary cast iron. High-chromium cast iron has been recognized as one of the best wear-resistant materials for abrasive wear and is increasingly being widely used.

The excellent wear resistance of high-chromium cast iron mainly depends on the characteristics of its matrix structure and the type and distribution of carbides.

High-chromium cast iron is a multi-component alloy composed mainly of Fe, Cr, and C. The matrix of freshly solidified high-chromium cast iron is austenite, which is stable only at higher temperatures and is saturated with elements such as C and Cr. As the temperature decreases, the austenite undergoes a transformation. Under normal conditions, high-chromium cast iron exhibits a multiphase structure predominantly composed of austenite. This type of structure enables the iron to better unleash its inherent potential when used at high temperatures.

High-chromium cast iron is a chromium-based white cast iron with a chromium content ranging from 12% to 28%. Our engineers have found that the addition of a large amount of chromium converts the M3C type carbides in white iron into M7C3 type carbides. These alloy carbides are extremely hard and provide high-chromium cast iron with excellent wear resistance. On the other hand, during the solidification process, the M7C3 carbides are distributed in a rod-like isolated manner, which improves the toughness of high-chromium cast iron to a certain extent.