Ceramic Ball
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Aluminium Oxide Ball
Aluminium Oxide Ball
Profile
Aluminium oxide (alumina) ceramic balls are the most widely used technical ceramic balls. With hardness far above any steel, low density, excellent wear and corrosion resistance, and electrical insulation, they excel in high-speed bearings, chemical pumps, valves and grinding media. Jiaxin supplies alumina balls from 0.3 mm to 250 mm in grades G3 to G60.
Hardness: HV 1500–1700 (HRA 85–90), far harder than any steel ball. Grades: Al2O3 92% / 95% / 99%, ISO 3290 Class I–III.
Sizes: 0.3 mm – 250 mm, with custom diameters available on request.
Applications:High-speed bearings, chemical pumps and valves, grinding media, flow meters and electrical insulators.
Why Jiaxin Alumina Ceramic Balls
Four advantages over typical alumina ceramic ball suppliers.
Widest Size Range
0.3 mm miniature to 250 mm large balls — far exceeding the typical 50.8 mm limit of most suppliers.
Bearing-Grade Precision
Grades G3 to G60, significantly tighter than industry-standard G20 or grade 1000, ideal for precision bearings
30 Years, Fortune 500
Three decades of manufacturing experience, trusted by Fortune 500 oil, gas and chemical companies worldwide.
ISO Certified Quality
Every batch ships with material certificate and inspection report. Passivation and custom packaging available.
Characteristics
Key material properties that make alumina the most widely used technical ceramic.
Extreme Hardness
HV 1500–1700 (HRA 85–90) — far harder than hardened steel, giving outstanding wear and abrasion resistance.
Lightweight
At ~3.9 g/cm³, roughly half the density of steel, alumina balls reduce centrifugal load in high-speed bearings.
Corrosion & Heat Resistant
Inert to most acids, alkalis and solvents and stable at temperatures up to 1500 °C.
Electrically Insulating
Alumina is an excellent electrical insulator, preventing arcing and electrolytic corrosion in bearings.
Chemistry
Reference composition of alumina ceramic ball grades.
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Aluminium oxide (Al2O3): 92% / 95% / 99% — determines hardness and wear resistance
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Silicon dioxide (SiO2): ≤ 5% (lower in 99% grades) — affects sintering and grain structure
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Calcium oxide (CaO): ≤ 2% — fluxing agent in lower-purity grades
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Magnesium oxide (MgO): ≤ 1% — grain growth inhibitor improving strength
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Sodium oxide (Na2O): ≤ 0.3% — controlled to avoid glassy phases
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Iron oxide (Fe2O3): ≤ 0.1% — impurity kept low for corrosion resistance
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Titanium dioxide (TiO2): ≤ 0.1% — trace impurity
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Loss on ignition: ≤ 0.5% — indicates full densification
Microstructure of sintered alumina ceramic balls showing fine, uniform grain structure.
Corrosion Resistance
Alumina balls offer exceptional resistance to acids, alkalis, solvents and molten metals. They do not rust, oxidise or leach, and are unaffected by seawater.
Not recommended for: hydrofluoric acid, hot concentrated phosphoric acid, or strong hot alkalis. For maximum toughness, consider zirconia; for thermal shock, silicon nitride.
Technical Specifications
Standard alumina ceramic ball specifications. Custom dimensions available on request.
Material Grade
Al2O3 92% / 95% / 99%
Precision Grades
G3, G5, G10, G16, G20, G28, G40, G60
Young's Modulus
~300 – 380 GPa
Surface Finish
Polished, lapped, or custom
Equivalent Names
Alumina, corundum, ISO 3290 Class I / II / III
Hardness
HV 1500–1700 (HRA 85–90)
Flexural
Strength~300-400 MPa
Supply Condition
Sintered, lapped and polished
Diameter Range
0.3 mm – 250 mm
Density
~3.6 – 3.9 g/cm³
Magnetism
Non-magnetic
Certification
ISO 9001, material certificate, inspection report
Material Selection Guide
Compare alumina with other common ball materials to choose the right one.
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Alumina — HV 1500–1700, lightweight, electrically insulating, lowest-cost ceramic. Best for chemical pumps and high-speed bearings. → Alumina product page
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420C — HRC 48-56, moderate corrosion resistance. Lower-cost martensitic option. → 420C product page
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304 — ~HRC 25, good corrosion resistance. General-purpose non-magnetic. → 304 product page
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316 / 316L — ~HRC 25, excellent corrosion resistance. Best for marine and chemical. → 316 product page
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52100 Chrome Steel — HRC 60-67, low corrosion resistance. Highest wear resistance at lower cost. → Chrome steel page
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Silicon Nitride (Ceramic) — Extremely hard, corrosion-proof, lightweight. For extreme environments. → Ceramic ball page
International Grade Equivalents
Alumina ceramic is known by different designations worldwide.
Common designation: Al2O3 92% / 95% / 99%
ISO 3290: Class I / II / III
Other names: corundum, aluminium oxide ceramic
Al2O3
92%
95%
99%
Class I
Class II
Class III
Corundum
Industries Using Alumina Ceramic Balls
Alumina balls are specified where hardness, chemical inertness, electrical insulation or light weight is required.
Chemical & Process
Chemical pumps, valves, flow meters, agitators and equipment handling acids, alkalis or ultrapure fluids.
Bearings & High Speed
High-speed spindle bearings, hybrid ceramic bearings, vacuum and cleanroom equipment, and electrically insulating bearings.
Grinding & Industrial
Grinding and milling media, ball mills, pigment dispersion, laboratory apparatus and wear-resistant components.
Lead Times & Ordering
Flexible supply for both standard and custom requirements.
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Standard sizes: Popular diameters in stock — typically 3-7 days for shipment.
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Custom orders: Lead time 15-30 days, based on diameter, grade and quantity.
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MOQ: Standard sizes have low MOQ. Custom sizes quoted per requirement.
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Packaging: Standard export packaging, or custom VCI bags, vacuum packing, bulk drums.
Technical Resources
Learn more about alumina ceramic ball selection and applications.
Frequently asked questions
Contact us! We reply within 24 hours, offer free procurement guidance, design to your needs, and provide a free sample
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