The materials of ball bearings for seated rolling bearings include steel used for raceway rings (outer ring, inner ring) and rolling elements (balls), and steel plates used for cages. These bearing materials should have the following characteristics. (1) Due to the large local contact stress, a high elastic limit is required. (2) Due to repeated exposure to large contact loads, high rolling fatigue strength is required. (3) High hardness can be obtained (4) Good wear resistance (5) Good toughness against impact load (6) Good dimensional stability The raceway ring (outer ring, inner ring) and rolling elements of ball bearings for seated rolling bearings (Ball) The material is generally high-carbon chromium bearing steel specified by JIS. The high-carbon chromium bearing steel has been vacuum degassed in order to improve the reliability of the bearing, reducing non-metallic impurities and lowering the oxygen content. The above bearing materials are generally processed into the required shape, and then quenched and tempered to increase the hardness to about 60HRC before use. The chemical composition of high carbon chromium bearing steel is shown in Table 12.1. The material of the raceway ring and rolling element of the stainless steel series component ball bearing (special symbol S6) uses stainless steel with excellent corrosion resistance. The material of the cage is cold-rolled steel plate and steel strip specified by JIS. The chemical composition of cold-rolled steel sheets and steel strips is shown in Table 12.2. The material of the bearing box The material of the bearing box for rolling bearing with seat mainly uses gray cast iron, carbon steel cast steel and structural rolled steel, cold-rolled steel plate and steel strip. Gray cast iron has better vibration absorption and attenuation performance than other materials. It is easy to obtain various shapes by casting, has appropriate strength, and has good thermal properties. It is the most general material for bearing housings for rolling bearings with seats. The mechanical properties of gray iron castings are shown in Table 12.3. When high strength is required for bearing housings for rolling bearings with seat, choose carbon steel castings with high breaking strength and impact resistance or rolled steel for general structures. The material of the bearing box for purification series components uses zinc alloy die-casting parts, and the material of the bearing box for stainless steel series components uses stainless steel castings. In addition, cold-rolled steel plates and steel strips are used as materials for the bearing housings for steel plate components. The mechanical properties of the above bearing housing materials are shown in Table 12.4 ~ Table 12.8. In addition to these materials, spheroidal graphite cast iron parts (FCD450-10 of JIS G5502) are sometimes used.