Ceramic balls

Ceramic balls are mainly used in harsh environments. Their main advantages on steel is that they have a density 40% lower than steel, have 29% lower thermal expansion and are 150% harder. In certain high-speed applications their life is extended hundred times. It is also used as grinding media. There are three main types.


 

Alumina Oxide - ceramic balls
Composition 99.5% Al2O3 / 0.5% other
Hardness 1700 Hv
Ultimate Tensile Strength 31,000 psi
Ultimate Compressive Strength >300,000 psi
Modulus of Elasticity 53 x106 psi
Maximum Working Temperature 1400oC
Corrosion Resistance Inert except for hydruofluric, hydrochloric acid and
hot concentrated sulphuric acids. Inert to most substances, not recommended for environments of strong alkaline solutions

 

Zirconia Oxide - ceramic balls
Composition 97% ZrO2 / 3% MgO
Hardness 80 - 84 Ra
Ultimate Tensile Strength 60,000 psi
Ultimate Compressive Strength 285,000 psi
Modulus of Elasticity 29 x106 psi
Maximum Working Temperature 2400oC
Corrosion Resistance Inert to most substances, not recommended for environments of hydrochloric or strong alkaline solutions

 

Silicon Nitride - ceramic balls
Composition 87% Si3N4 / 13% other
Hardness 1400 - 1700 Hv
Ultimate Tensile Strength /
Ultimate Compressive Strength >570,000 psi
Modulus of Elasticity 44-45 x106 psi
Maximum Working Temperature 1000oC
Corrosion Resistance Inert to most substances.