Bearing material detection

Bearing material is a key factor in determining bearing life and related performance (such as impact resistance, high temperature resistance, etc.). For finished bearings, the most important indicators to be controlled in terms of materials are hardness and metallographic structure.

Hardness: Bearing steel is generally made of high-carbon and high-chromium materials (such as GCr15), and its hardness can reach about 60HRC after processing to the finished bearing. If the hardness is too low, the bearing is easy to wear during use, while if the hardness is too high, the brittleness of the material will increase and fracture is easy to occur during use. Therefore, the hardness of the finished bearing is one of the key quality control indexes when the finished product leaves the factory.

Metallographic microstructure: the bearing will involve forging processing and heat treatment processing in the whole manufacturing process (and the raw materials themselves have acceptance requirements). If these thermal processing processes are not properly controlled, they will have serious consequences for the final finished bearing (such as bearing ring fracture, steel ball fracture, etc.), so the control of metallographic structure becomes an important means and method at this time, the evaluation and control of the material organization can be achieved by observing the microstructure and comparing the rating with the standard map.

The measurement method and limit requirements (index compliance) of bearing hardness and metallographic microstructure are clearly stipulated in the relevant national standards, and the inspection can be judged according to the relevant requirements.