Views: 0 Author: Site Editor Publish Time: 2026-07-24 Origin: Site
AISI 420 stainless steel balls are hardened martensitic stainless steel balls designed for applications that require higher hardness, good wear resistance, magnetic properties and moderate corrosion resistance.
As a professional stainless steel balls manufacturer in China, RISHENG supplies AISI 420 stainless steel balls for bearings, valves, pumps, automotive components, hardware, polishing media, lighters, ballpoint pens and precision mechanical assemblies. We offer custom sizes, precision grades, bulk packing and OEM/ODM production for global industrial buyers.
Compared with 304 and 316 stainless steel balls, 420 stainless steel balls provide much higher hardness after heat treatment. Compared with 440C stainless steel balls, AISI 420 offers a more cost-effective choice for medium-load applications where extreme bearing-grade hardness is not required.
AISI 420 stainless steel balls are made from martensitic stainless steel. This material can be hardened by heat treatment, which gives the balls higher strength and better wear resistance than austenitic stainless steel balls such as 304 and 316.
The main advantages of 420 stainless steel balls include:
High hardness after heat treatment
Good wear resistance
Magnetic properties
Smooth polished surface
Better hardness than 304/316 stainless steel balls
Lower cost than 440C stainless steel balls
Suitable for water, steam, air and mild industrial environments
Hardness is one of the most important reasons buyers choose AISI 420 stainless steel balls. After heat treatment, 420 stainless steel balls can usually reach around HRC 50–55, depending on the exact size, material condition and customer requirements.
| Material | Typical Hardness | Magnetic | Corrosion Resistance |
|---|---|---|---|
| 304 Stainless Steel Balls | HRC 25–39 | Weak / slight | Good |
| 316 Stainless Steel Balls | HRC 25–39 | Weak / slight | Very good |
| 420 Stainless Steel Balls | HRC 50–55 | Yes | Moderate |
| 440C Stainless Steel Balls | HRC 58–65 | Yes | Moderate |
RISHENG manufactures AISI 420 stainless steel balls in common metric and inch sizes. Custom diameters can also be produced according to drawings, samples or application requirements.
| Item | Available Options |
|---|---|
| Material | AISI 420 / 420C stainless steel |
| Size Range | Custom small and medium sizes available |
| Precision Grades | G10, G16, G25, G40, G100, G200, G500, G1000 |
| Surface Finish | Polished / high polished |
| Hardness | HRC 50–55, customizable by requirement |
| Standard | ISO 3290, GB/T 308.1, customer standard |
| Supply Type | Bulk wholesale, OEM, ODM, factory direct supply |
Popular sizes of AISI 420 Stainless Steel Ball include:
| Metric Size | Inch Equivalent | Common Applications |
|---|---|---|
| 1.588 mm | 1/16" | Small mechanisms, ballpoint pens |
| 2.381 mm | 3/32" | Precision components |
| 3.175 mm | 1/8" | Valves, pumps, bearings |
| 4.763 mm | 3/16" | Hardware, automotive parts |
| 6.35 mm | 1/4" | Bearings, check valves |
| 7.938 mm | 5/16" | Industrial assemblies |
| 9.525 mm | 3/8" | Pumps, valves, machinery |
| 12.7 mm | 1/2" | Medium-load mechanical parts |
420 stainless steel balls can be used in stainless bearings, light-duty bearings, guide systems and precision mechanical assemblies. They are suitable for applications where hardness is more important than strong chemical corrosion resistance.
Because 420 stainless steel balls offer good hardness and polished surface quality, they are commonly used in check valves, ball valves, pump components, flow meters and fluid control systems.
420 stainless steel balls are used in automotive seatbelt mechanisms, lighters, locks, drawer slides, casters, hardware parts and small mechanical devices.
Small 420 stainless steel balls are often used in ballpoint pen tips, cosmetic applicators, spray systems and other consumer products that require smooth movement and wear resistance.
For non-aggressive environments, 420 stainless steel balls can also be used as polishing media or light-duty grinding media.
| Buyer Requirement | Recommended Material | Reason |
|---|---|---|
| General corrosion resistance | 304 stainless steel balls | Cost-effective and widely used |
| Marine or chemical environment | 316 stainless steel balls | Better chloride and chemical resistance |
| Higher hardness and wear resistance | 420 stainless steel balls | Hardened martensitic stainless steel |
| Bearing-grade hardness | 440C stainless steel balls | Highest hardness among common stainless steel balls |
| Magnetic stainless steel balls | 420 / 440C stainless steel balls | Martensitic stainless steel, magnetic |
| Food or medical non-hardness applications | 304 / 316 stainless steel balls | Better corrosion resistance |
Changzhou Risheng Steel Ball Co., Ltd. is a precision steel ball manufacturer supplying stainless steel balls, chrome steel balls, carbon steel balls, copper balls and custom special-shaped balls for global customers.
As a factory-direct AISI 420 stainless steel balls supplier, RISHENG can support:
Bulk wholesale orders
Custom sizes and precision grades
OEM/ODM production
Hardness and dimensional inspection
Polished surface finish
Stable lot-to-lot quality
Export packing for long-distance shipping
Fast quotation based on size, grade, quantity and application
For buyers searching for 420 stainless steel balls manufacturer, AISI 420 stainless steel balls supplier, or hardened stainless steel balls factory, RISHENG provides a direct manufacturing solution with flexible customization.
What is the hardness of AISI 420 stainless steel balls?
AISI 420 stainless steel balls usually reach around HRC 50–55 after heat treatment. The exact hardness depends on the ball size, heat treatment process and customer requirement.
Are 420 stainless steel balls magnetic?
Yes. AISI 420 is martensitic stainless steel, so 420 stainless steel balls are magnetic.
Are 420 stainless steel balls corrosion resistant?
420 stainless steel balls have moderate corrosion resistance. They are suitable for water, steam, air and mild environments, but they are not the best choice for strong acids, saltwater or chemical environments.
What are 420 stainless steel balls used for?
They are widely used in bearings, valves, pumps, flow meters, automotive parts, lighters, ballpoint pens, hardware, locks, casters and polishing applications.
What is the difference between 420 and 440C stainless steel balls?
420 stainless steel balls offer good hardness and lower cost. 440C stainless steel balls provide higher hardness, better wear resistance and are more suitable for high-load precision bearing applications.
Can RISHENG supply custom 420 stainless steel ball sizes?
Yes. RISHENG can produce custom AISI 420 stainless steel balls according to diameter, precision grade, hardness, surface finish, quantity and application requirements.
