THRUST NEEDLE ROLLER BEARING, SUPPORT STRUCTURE RECEIVING THRUST LOAD OF COMPRESSOR FOR CAR AIR-CONDITIONER, SUPPORT STRUCTURE RECEIVING THRUST LOAD OF AUTOMATIC TRANSMISSION, SUPPORT STRUCTURE FOR NONSTEP VARIABLE SPEED GEAR, AND SUPPORT STRUCTURE RECEIVING THRUST LOAD OF MANUAL TRANSMISSION

摘要

A thrust needle roller bearing (10A) having a bearing washer (1) made from a thin steel plate and a needle roller (2), wherein at least the bearing washer (1) has a nitrogen-rich layer in its surface layer portion, and the surface layer portion contains retained austenite in an amount of 5 to 25 vol % and has an austenite grain size number of 11 or higher. The above thrust needle roller bearing exhibits good resistance to the early failure by the damage of a surface such as the exfoliation starting from the surface and to the general fatigue owing to rolling and depending on the load imposed thereon, and thus has a long life.