The alumina wear-resistant engineering ceramics used in the cement industry have excellent properties such as high melting point, high hardness, high compressive strength, low density, wear resistance, corrosion resistance, oxidation resistance, and minimal creep at high temperatures. During application, it is best to avoid using them under working conditions with high stress and large-angle impacts.
3.2.1 Wear-resistant ceramic tiles
3.2 Ceramic wear-resistant materials
Divided into low alloy steel, medium alloy steel, and high alloy steel. Wear-resistant alloy steel can obtain the necessary impact toughness and hardness indicators of the material by adjusting the chemical composition and heat treatment process. The hardness can reach HRC = 52～58, and the impact toughness can reach ak = 15～30J/cm².
3.1.3 Wear-resistant alloy steel series
3) Low-chromium alloy white cast iron. Compared to ordinary white cast iron, this type of cast iron has better stability of carbides when used for wear-resistant materials in sand-making equipment.
2) Chromium-based white cast iron (commonly referred to as high-chromium cast iron) with good wear resistance. This type of cast iron contains 12%～20% chromium, along with an appropriate amount of molybdenum. When the matrix is entirely martensite, this alloy exhibits the best wear-resistant performance. If residual austenite exists in the matrix, heat treatment is typically required.
Based on its microstructure and usage, chromium-based cast irons can be classified into three categories: 1) Chromium-based white cast iron with good high-temperature performance. This type of cast iron contains 33% chromium and often features a structure composed mainly of austenite and iron-chromium carbides, sometimes also containing ferrite. Besides having certain wear resistance, this alloy also demonstrates good oxidation resistance under working conditions at temperatures not exceeding 1050℃.
3.1.2 Anti-wear high-chromium cast iron series
Under strong impact loads or contact stresses, the surface layer of high-manganese steel rapidly hardens, with the hardness increasing sharply from HBS200 to 400～550, thereby creating a highly wear-resistant surface layer. Meanwhile, the core austenite retains excellent toughness, preserving the original mechanical properties. As one layer hardens and wears away, the next sub-layer becomes hardened until it reaches the failure state. The heavier the impact on the surface, the more complete the surface hardening, resulting in better wear resistance. If the surface does not receive sufficient impact force, it cannot fully harden, leading to a lack of wear resistance and exhibiting non-wear-resistant characteristics.
High-manganese steel series
Metal wear-resistant materials
3 Basic properties of commonly used wear-resistant materials
3) Low-stress abrasive wear. This type of wear is characterized by low stress, where the abrasive exerts stress on the friction surface that does not exceed its own crushing strength. The material surface shows scratches and tiny cutting marks. For instance, the wear on the impeller of a mud pump.
2) High-stress abrasive wear. This type of wear is characterized by high stress, where the stress endured by the abrasive exceeds the crushing strength of the abrasive. The crushed abrasive particles are polyhedral, scratching the metal and leaving grooves and craters on the friction surface. For example, the damage on the surfaces of jaw plates in ore crushers.
1) Chisel-type abrasive wear. This type of wear is characterized by high impact force, where the abrasive cuts into the metal surface with great impact, chiseling off large metal particles, producing deep grooves and indentations on the worn surface. For instance, the wear on the hammerhead and other components' surfaces in ore crushers.
Abrasive wear can be classified based on the stress and impact size experienced by the material's surface into chisel-type abrasive wear, high-stress abrasive wear, and low-stress abrasive wear.
Abrasive wear refers to the process of material surface loss caused by the interaction between abrasive particles or hard micro-protrusions and the surface material. For example, the wear caused by the relative motion friction between equipment components and ores, sand, soil, clinker, coal, etc.
Material wear can be categorized by mechanism into abrasive wear, impact wear, sliding wear, contact fatigue wear, fretting wear, erosion wear, adhesive wear, and abrasive-corrosion wear, among which abrasive wear accounts for over 50% of all wear-related losses. In the cement industry, most wear occurs primarily through abrasive wear mechanisms.
Material wear mechanisms
Erosion environment refers to the contact method between the eroded object, wear-resistant materials, and erosive substances, their relative motion state, mutual interaction relationship, and the shared cavity they occupy, along with the temperature and humidity within it. Products in China's mining equipment industry, such as sand-making equipment and mineral processing equipment, are severely eroded during production. Especially sand-making machines, sand washing machines, vibrating screens, rod mills, and jaw crushers in sand-making equipment, which are in long-term frictional contact with stones or other materials during production, are easily eroded. Therefore, the quality of domestically produced mineral processing and sand-making equipment is closely related to the product's corrosion resistance.