Choosing proper material from which bearings will be manufactured has great influence on:
- bearings durability under work condition,
- load carrying ability under required revolutions,
- condition of working surfaces after prolonged period of time.
Material used for bearing such be characterized by great fatigue and wear resistance.
Bearing rings and rolling elements are manufactured from special chromium steel 100Cr6 or 100CrMnSi6-4 or 100CrMnMoSi8-4-6.
The 100Cr6 steel is used for bearings components with smaller cross-section and 100CrMnSi8-4-6 with greater manganese content and better hardenability finds application in bearings elements with greater cross-section. For special purposes, where great reliability is a must bearing rings and rolling elementsare manufactured from vacuum degassed steel or electroslag remelted steel.
Rolling elements and bearing rings undergo special heat treatment which allows to obtain hardness in the range of 59-65 HRC and ensures dimension stabilization up to 150°C. On special demand bearings can be stabilized for work in higher temperatures.
Bearings cages for general purposes bearings with small and medium sizes are manufactured in big series from non-hardened steel or brass sheets. Nevertheless, thermoplastics are more and more common material used for cages manufacturing.
For bearings with greater sizes and for those working in special environment there are often employed solid brass cages. In case of great revolution speed there are usually used light solid cages made from aluminium alloys or plastic cages (polyamide, textolite, etc.).
