Material Guide
Compare common stainless steel grades used in bearings and related components, including 304, 316, 420, 440C, and 17-4PH. Review corrosion resistance, hardness, magnetism, and typical application considerations.
Quick Material Comparison
A high-level overview of the most common stainless steel grades used in our assemblies.
Not all products are available in all materials. Availability varies by product type and structure. Please confirm on the relevant product page or during inquiry.
Material Profiles
304 Stainless Steel
A widely used stainless steel grade for general industrial environments. Often selected where general corrosion resistance, manufacturability, and cost balance are important.
316 Stainless Steel
Commonly selected for environments involving salt, chlorides, humidity, washdown, or outdoor exposure. Often referred to as marine-grade stainless.
420 Stainless Steel
A martensitic grade that provides higher hardness and strength than 300 series. Often considered for parts where wear resistance matters but cost must be controlled.
440C Stainless Steel
A high-carbon martensitic stainless steel used where high hardness and wear resistance are critical, like bearing balls, races, and fatigue surfaces.
17-4PH Stainless Steel
Often selected where a project requires higher strength together with useful corrosion resistance. May be considered for selected stems, shafts, or structural parts.
Side-by-Side Property Matrix
| Property | 304 A2 |
316 A4 |
420 | 440C | 17-4PH |
|---|---|---|---|---|---|
| Structure Type | Austenitic | Austenitic | Martensitic | Martensitic | PH Stainless |
| Magnetism | No / trace | No | Yes | Yes | Yes |
| Corrosion Resistance | Good | Excellent | Moderate | Moderate | Good |
| Hardness Potential | Low | Low | Medium to high | High | Medium to high |
| Wear Resistance | Low | Low | Medium | High | Medium |
| Marine / Chloride | Limited | Better choice | Not preferred | Not preferred | Project-dependent |
| Typical Cost | $ | $$ | $ | $$ | $$$ |