Ball Bearing Material

There are essentially two choices for the material used in ball bearings - chrome steel or stainless steel. Since the material plays a major part in the performance of a bearing in any given application, it is very important that the correct material is used. Note that the specified material applies to the load bearing components only - the rings and the balls. The retainer and the shields (if used) are usually made from a different material and are subject to separate specification.

This is the standard material used for ball bearing applications where load capacity is the main consideration. The machinability of this steel is excellent, giving smooth, low noise raceway finishes, together with superior life. Chrome steel material is recommended in applications where corrosion is not a factor.

C CARBON	Si SILICON	Mn MANGANESE	P PHOSPHOROUS	S SULPHUR	Cr CHROMIUM	Mo MOLYBDENUM
.95 - 1.1	.15 - .35	Max .5	Max .025	Max .025	1.3 - 1.6	-

The use of 440C material has declined in favor of other, more modern stainless steel formulations. However, it is still widely available and has very high resistance to corrosion.

C CARBON	Si SILICON	Mn MANGANESE	P PHOSPHOROUS	S SULPHUR	Cr CHROMIUM	Mo MOLYBDENUM
.95 - 1.2	Max 1.0	Max 1.0	Max .04	Max .03	16 - 18	Max .75

Higher corrosion resistance than AISI 440C stainless steel ball bearings

Specic Gravity	Tensile Strength(N/mm2)	Elongation	Elastic Modulus(N/mm2)	Hardness	Magnetism
7.93	520 ～ 600	45％ ～ 60％	193000	170 HV 3.0 HRC	Non magnetic*1

Better corrosion resistance than 440c, 304 stainless. Resists sodium and calcium brines, hypochlorite solutions, phosphoric acid, sulfite liquors and sulfurous acids that are commonly used in the paper pulp industries.

Carbon	Manganese	Phosphorus	Sulfur	Silicon	Chromium	Nickel	Nitrogen	Molybdenum
Maximum of 0.080%	Maximum of 2.00%	Maximum of 0.045%	Maximum of 0.030%	Maximum of 1.00%	16.00% to 18.00%	10.00% to 14.00%	Maximum of 0.010%	2.00% to 3.00%