| FOR REQUIREMENTS: | Stainless Bearing Steel |
| MELT PRACTICE: | VAR and Air-Melt |
| SPECIFICATIONS & DESIGNATIONS: | AMS: 5630 (Air-Melt), 5880 (Air-Melt), 5618 (VAR) DIN: 1.4125, 1.3544 EN: X105CrMo17, X102CrMo17 UNS: S44004 AFNOR: Z100CD17 |
Get 440C Stainless Bar and Wire at Sullivan Steel
Need 440C steel? We stock domestic-melted round bar and wire in the following specs and sizes:
- AMS 5618 (VAR) Bar: 0.125″ø – 6.000″ø
- AMS 5618 (VAR) Wire: 0.135” – 0.218” ø
- AMS 5630 / AMS 5880 (Air-Melt) Bar: 0.25″ – 6.50″
Additional small diameter bar and wire sizes are available upon request.
Chemical Composition
| C | Si | Mn | Cr | Mo | S | P | |
|---|---|---|---|---|---|---|---|
| min. | 0.95 | – | – | 16.00 | – | – | – |
| max. | 1.20 | 1.00 | 1.00 | 18.00 | 0.75 | 0.030 Air-melt 0.010 VAR |
0.040 Air-melt 0.020 VAR |
Corrosion Resistance
As a stainless steel, 440C is a great go-to grade for many applications where moderate corrosion resistance is needed, offering superior performance to 52100.
In certain extreme environments, however, components made of 440C can still corrode. When superior corrosion resistance is required, we recommend grades like XD15NW® and XD16N.
You can learn more about 440C alternatives for better corrosion resistance in our guide on corrosion resistant bearing steels.
Heat Treatment
As a steel with relatively high hardness, 440C is often annealed for easier machinability. Following this, 440C can be hardened and quenched to increase strength and prevent cracking. Tempering can be performed to reduce brittleness without sacrificing hardness.
Mechanical Properties
Note that mechanical properties for 440C range depending on the steel’s tempering temperature.
| Hardness | Rockwell C 60 after heat treatment/tempering |
| Ultimate Tensile Strength | 285 ksi / 1965 MPs at room temperature |
| 0.2% Yield Strength | 275 ksi / 1896 MPs at room temperature |
| Machinability | Machinability for 440C is typically best in the annealed condition |
440C Applications
- Cutting Instruments
- Ball Bearings and Ball Screws
- Knife Blades, Chisels, and Swords
- Surgical Instruments
