Si3N4 ceramic ball

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    Silicon nitride ceramic (Si3N4) is a new kind of bearing material with several good features, it possesses high temperature resistance, corrosion resistance, insulation, non-magnetism, high strength, low density and other features. In the application of bearing, it possesses low friction, low temperature rise, high rigidity, low centrifugal force and other features. It can implement high speed, high precision, high temperature, high rigidity, corrosion resistance and other good features.

    Silicon nitride ceramic ball with high precision and high performance  is manufactured by  spray-drying process, near-net-shape, cold isotatic pressing, GPS-HIP combined sintering, compounded abrasive lapping process effectively. The precision grade of it is G5, the materials class is I.

    Si3N4 ceramic ball material grades
    

    Class		Materials class
    Item		I	II	III
    Property	Bending strengthσ3.40(Mpa)	900	800	600
    	Crushing load ratio(%)	35	35	30
    	Hardness(HV10)	1580	1480	1380
    	Fracture toughness(Mpa.m1/2)	6.0	5.0	5.0
    The limit does of fiber structure	Pore size(μm)	10	10	25
    	Porosity(%)	0.02	0.06	0.06
    	Crystal phase(μm)	10	10	25
    	The second ceramic phase(μm)	25	25	25
    The maximum of inclusion of transverse section every Square centimeter	Range 200(μm)	0	0	1
    	Range 100～200(μm)	0	1	2
    	Range 50～100(μm)	1	2	4
    	Range 20～50(μm)	4	8	16

    Examples of Si3N4 Silicon nitride ceramic ball common applications
    

    	G3	G5	G10 G16	G20 G28 G40
    Class I	High speed power equipment Space mechanism Aircraft instrument	Liquid oxygen pump Active shaft bearing
    Class II
    Class III			Sport, entertainment, food processing	Mechanical devices

    Si3N4 ceramic ball specifications
    

    The nominal diameter of bearing ball		The nominal diameter of bearing ball		The nominal diameter of bearing ball
    mm	in	mm	in	mm	in
    0.794	1/32	5		8.731	11/32
    0.8		5.5		9.525	3/8
    1		5.556	7/32	11.112	7/16
    1.588	1/16	5.953	15/64	12.303	31/64
    2		6		12.7	1/2
    2.381	3/32	6.35	1/4	13.494	17/32
    2.5		6.5		14.288	9/16
    3		6.747	17/64	15.081	19/32
    3.969	5/32	7		15.875	5/8
    4		7.144	9/32	19.05	3/4
    4.5		7.5		25.4	1
    4.762	3/16	7.938	5/16	31.75	1 1/4

    Note:The special specification can be manufactured after negotiating