BALL BEARING MATERIAL OPTIONS

Rings and Balls

SAE 52100 – This is the most commonly used high quality bearing material and contains 1% carbon and 1.5% chromium.  It offers good wear resistance.  The standard stabilization temperature range for aircraft bearings utilizing SAE 52100 is -65º F to 250º F.  Special heat treatment can increase the maximum operating temperature to 400º F.

440C – The most commonly used stainless steel bearing material.  It is fully hardenable (Rc 58 -61) and offers moderate wear resistance and can be used in moderately corrosive environments.  The standard maximum operating temperature for Schatz aircraft bearings utilizing 440C is 300º F.  Special heat treatment can increase the maximum operating temperature to 450º F. 

440C Modified – This material offers corrosion resistance for applications requiring high operating temperatures.  Maximum operating temperature is 850º F.

XD15NW (EMS138 in graphs below) – This is a stainless bearing steel that offers very good corrosion resistance and excellent wear resistance. Standard heat treatment for Schatz aircraft bearings utilizing this material allow for operating temperatures of up to 300º F. A special heat treatment can be applied to allow for operating temperatures of up to 850º F.

M50 – This is an aerospace bearing material that offers excellent fatigue and wear resistance at moderately high operating temperatures.  The maximum operating temperature for bearings utilizing this material is 600º F.

BG42 – A high performance, martensitic, high speed stainless steel designed for critical aerospace and bearing applications. BG42 combines the hot hardness characteristics of M-50 and the corrosion resistance of 440C Stainless.

XD16N – A good alternative to BG42, XD16N is a high Nitrogen Martensitic Stainless Steel for corrosion, temperature, and wear resistance. This grade is an air-melt only, less costly version of XD15NW, yet still offers greatly superior corrosion resistance to 440C or 440C VAR.

Hybrid bearings with steel rings and ceramic balls – Bearings utilizing steel inner and outer rings with ceramic rolling elements offer higher speed capability, higher stiffness, and extended wear life.

Fatigue Resistance Chart

Corrosion Resistance Chart