FAG bearings are usually used to support the shaft journal and the rotary member, usually from the inside rings, outer ring, rolling elements (balls, rollers, tapered roller or needle) and hold other components. FAG bearings used in the manufacture of steel, called FAG bearing steel.
FAG bearing steel:
FAG Bearings work when the machine rotating portion and the fixed portion of the load between the rolling elements pass through. Between theory, race and rolling bodies as a point (or line) contacts are under concentrated load, contact stress is usually up to 1 500 --- 5 000 MPa. When bearing operation, the bearing points bear a tensile cycle compression load, the force from zero to reach the maximum, and then from the maximum to zero, periodically increase and decrease, and the maximum number of cycles (typically tens of thousands of times / min ʱ?? The race, in addition to the rolling element rolling, there is relative sliding, resulting in rolling friction and sliding friction.
In some cases, the bearings will be subject to certain sophisticated torsion or impact.
Therefore, FAG bearing failure modes are mainly contact fatigue damage (mostly pitting, spalling) and wear.
For bearings can work, without early failure, FAG bearings must have a high hard R (69HRC above) and high wear resistance; has a high compressive strength and contact fatigue strength; good dimensional stability and a certain corrosion sex. For bearings used under special conditions, it should also have heat resistance, high corrosion resistance.
Chromium bearing steel FAG bearing parts are manufactured, as well as other major steel parts and bearing parts FAG used similar working conditions, in which the largest amount of GCr15 steel, followed GCr15SiMn. Mass fraction of carbon chromium bearing steel is 0.95% ^ -1.05%, high carbon content of the steel after quenching with high strength, hardness and wear resistance.
Chromium can improve the steel hardenability. In the carbon mass fraction of 1% of hypereutectoid steel, chromium can significantly improve the steel and carbide particle size distribution. Chromium bearing steel quenching, tempering, has good wear resistance, strength, elastic limit and yield strength.
Chromium bearing steel, manganese content up to. .9% To 1.2%, mass fraction of silicon increased to 0.40% - 0.70%, with the steel of this ingredient, such as GCr9SiMn and GCr15SiMn, hardenability, tempering resistance and strength were improved, The toughness is not reduced.