Metallurgical defects such as non-plastic inclusions in metals have a serious impact on fatigue and wear. Angled particles, such as nitrides, oxides, and silicates in steel, cannot deform in coordination with the matrix to form voids during stress, forming a source of stress concentration, and cracks and expansion under the action of alternating stress In the end, fatigue and wear appear early.
Therefore, the selection of metal materials with less harmful inclusions is of great significance to improve the anti-fatigue wear resistance of friction. The material factors of the grinding roller include chemical composition, mechanical properties, etc. The surface layer should not have manufacturing defects such as pores, sand holes, cracks, and uneven hardness.
In general, the material's ability to resist fatigue wear increases with the increase of surface hardness, and once the surface hardness exceeds a certain value, the anti-wear performance will decrease. For the grinding roller, it involves frequent roughening of the surface, Therefore, it is necessary to consider the machining performance when increasing the hardness.
The hardness of the core of metal parts has a certain effect on fatigue wear. Under the condition of a certain external load, the higher the hardness of the core, the lower the risk of fatigue cracks. The grinding roller is subjected to a large radial force and requires a certain toughness of the roller body. The core is generally made of gray cast iron . Therefore, the hardness of the core should be reasonably increased, but it cannot be increased indefinitely, otherwise the toughness is too low and cracks are likely to occur.
In addition, the thickness of the hardened layer of the outer layer of white iron also has an effect on the ability to resist fatigue and wear. When the hardened layer is too thin, fatigue cracks will appear at the connection between the hardened layer and the substrate and easily form surface peeling. Therefore, when choosing the thickness of the hardened layer, fatigue cracks should be generated in the hardened layer to improve the ability to resist fatigue and wear.