Stainless Steel Balls Manufacturer in China - 201 to 440C OEM Supply

Five stainless steel ball grades cover over 90% of industrial applications, from economical hardware balls to bearing-grade precision balls. Select a grade for full specifications, or ask our engineers for free material selection support.

Use this stainless steel balls selection guide to match the grade to your application — corrosion environment, required hardness and magnetic requirements decide the choice. The comparison table below summarizes the differences.

304 Stainless Steel Ball（AISI 304 / SUS 304）
- Most versatile and economical austenitic 304 stainless steel ball
- Composition: 18% Chromium + 8% Nickel (18-8 stainless steel)
- Characteristics: Excellent corrosion resistance, non-magnetic (very weak magnetism after demagnetization), good toughness and ductility
- Corrosion resistance: Suitable for general corrosive environments such as atmosphere, water, steam, grease, and food.
- Unsuitable for: Strong corrosive environments such as those with high chloride ion resistance (e.g., seawater, salt spray).
- Common applications: Furniture drawer slides, spray bottle pump heads, food processing equipment, low-load bearings, cosmetic mixing balls, etc.
- Hardness: HRC ≤ 26 (annealed state)

316 Stainless Steel Ball（AISI 316 / SUS 316 / 316L）
- Medical-grade and marine-grade stainless steel balls
- Composition: 16-18% Chromium + 10-14% Nickel + 2-3% Molybdenum (molybdenum-containing stainless steel)
- Features: Superior resistance to pitting and chloride ion corrosion compared to 304; resistant to seawater, salt spray, acids, and alkalis; low magnetic or non-magnetic
- Common specifications: 316 and lower carbon 316L (carbon content ≤0.03%) are interchangeable; 316L is more suitable for welding applications.
- Common applications: Medical devices, pharmaceutical equipment, marine environment parts, jewelry, spray pumps, high-end cosmetic bottle pump heads
- Hardness: HRC ≤ 26

420 Stainless Steel Ball（AISI 420 / SUS 420）
- Magnetic martensitic stainless steel balls, heat-treatable
- Composition: 12-14% chromium, carbon content above 0.15%
- Features: Some corrosion resistance (not as good as 304/316), but can achieve higher hardness through quenching and tempering
- Hardness range: HRC 50-58 (after quenching)
- Advantages: Good wear resistance, moderate cost, strong magnetism
- Common applications: Medium to high load bearings, slide rails, power tools, valves, nail clippers, and other applications requiring a certain level of hardness.

440 Stainless Steel Ball（AISI 440C / SUS 440C）
- Highest hardness and wear resistance stainless steel balls
- Composition: 16-18% chromium, carbon content 0.95-1.2%
- Features: Can be quenched to maximum hardness; corrosion resistance is still better than the 420 series, but not as good as 316.
- Hardness: HRC 58-65 (440C can reach HRC 60+)
- Common grades: 440A, 440B, 440C (440C has the strongest hardness and wear resistance)
- Applications: High-end precision bearings, aerospace parts, surgical instruments, high-precision valves, military products

RISHENG manufactures precision stainless steel balls, SS balls, stainless steel spheres and stainless bearing balls in multiple material grades, diameters, tolerance levels and surface finishes. As a stainless steel ball factory and OEM supplier in China, we support custom sizes, bulk orders, wholesale supply, OEM packaging and inspection reports for global buyers.

RISHENG manufactures stainless steel balls from 0.8 mm to 25.4 mm in both metric and inch sizes. The most frequently ordered precision stainless steel ball diameters are listed below. Non-standard sizes, custom OEM sizes and bulk stainless steel ball orders are available on request.