Abrasion-Resistant Flow-Passing Component Materials
The material used for the flow-passing components of slurry pumps is high-chromium alloy. With technological and environmental demands continuously increasing, the requirements for materials are also rising. Research on hypereutectic high-chromium cast iron has revealed that most current studies on high-chromium white cast iron are limited to the hypoeutectic or eutectic range. For example, China's national standard for wear-resistant materials includes KMTBCr26 cast iron, a hypoeutectic high-chromium cast iron known for its high wear resistance and certain toughness, making it suitable for producing complex-shaped castings such as the flow-passing components of slurry pumps. Although hypoeutectic high-chromium cast iron is regarded as one of the best wear-resistant materials available today, its service life is considerably short under highly abrasive working conditions, sometimes lasting only several dozen or a hundred hours.
Hypereutectic high-chromium cast iron features relatively high carbon and chromium content, leading to a significant increase in the volume of carbides within the material and a considerable improvement in hardness. This plays an important role in enhancing wear resistance. However, when the carbide content exceeds a certain level, coarse primary carbides form in the high-chromium cast iron, resulting in a sharp decline in toughness. During casting production, this leads to high rejection rates due to cracking defects. Therefore, hypereutectic high-chromium cast iron is currently mainly used to produce castings with simple shapes applied under low-stress abrasion conditions. By refining the primary carbides in hypereutectic high-chromium cast iron and promoting a globular distribution of carbides, the impact toughness can be improved. This makes it possible to apply hypereutectic high-chromium cast iron in slurry pump components and will further enhance the performance of high-chromium cast iron.