Selection principles of rolling bearing steel

When designing and manufacturing rolling bearings, the selection of bearing materials is generally based on the following principles.

1、 Select according to the working conditions of the bearings

①. Working temperature

Bearings working at room temperature are made of chromium bearing steel. Chromium bearing steel is also used for working temperatures above 150 ℃ and below 250 ℃, but it needs to undergo special heat treatment (requiring tempering at 200 ℃ or 300 ℃).

②. The magnitude of the impact load to be borne

Bearings that withstand strong impact loads generally do not use chromium bearing steel, but mostly use high-quality carburized structural steel, impact resistant tool steel, or quenched and tempered structural steel.

③ Contact medium

Bearings used in corrosive media must be made of corrosion-resistant steel or alloy steel with good corrosion resistance.

2、 Select according to the structural type of the bearing

The structure of bearing components is relatively complex, such as the outer ring with installation flanges, and when subjected to high impact loads, it is advisable to use carburized steel with good machining performance; The outer ring of the stamped needle roller bearing can be made of 08 and 10 low-carbon steel (with good plasticity and suitable for cold stamping processing); Joint bearings used on swing or control mechanisms can be formed by cold extrusion of GCr15, 9Cr18, 9Cr8Mo and alloy structural steel with excellent cold plastic deformation performance.

3、 Select based on bearing fatigue life and reliability requirements

The fatigue life and reliability of bearings depend to a certain extent on the purity and uniformity of the steel structure. For general use, ordinary bearing steel smelted in acidic open hearth or alkaline electric furnace is often used. With the continuous improvement of smelting methods, new smelting methods such as current remelting, vacuum smelting, and electron beam furnace smelting have emerged. Bearings made of bearing steel refined by these methods have correspondingly increased their lifespan. Suitable for bearings with special requirements for fatigue life and reliability, such as railway vehicle axle box bearings, aviation engine spindle bearings, and navigation system bearings.

In addition, when selecting steel grades, comprehensive consideration should also be given to the processing performance, supply of goods, and domestic resource situation of the steel.