· Silicon nitride ceramic ball compared with steel, silicon nitride quality than steel is light, coefficient of friction is small, good sports performance, modulus of elasticity is 50% greater than steel, not only the coefficient of thermal expansion of silicon nitride is less than 25% of steel, high temperature in the 1000 ° C before the high strength and hardness, corrosion-resistant, non-rusting, non-magnetic, and can be in the oil lubrication under the conditions of work.
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