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Product Overview
AISI 440C is a high-carbon martensitic stainless steel designed to provide stainless properties with maximum hardness. At Jaron Steel, our 440C round bars are engineered for environments where extreme wear resistance and moderate corrosion resistance are required. After professional heat treatment, it can reach a Rockwell hardness of HRC 60, making it one of the hardest stainless steels available on the market.
Key Performance & Advantages
- Extreme Wear Resistance: The high carbon content forms hard chromium carbides, protecting the steel from abrasive wear.
- Excellent Edge Retention: Perfect for cutting tools and surgical instruments that must remain sharp for long periods.
- Moderate Corrosion Resistance: Resistant to fresh water, steam, crude oil, gasoline, and mild acids when fully hardened and polished.
- High Compressive Strength: Ideal for heavy-load bearing applications.
Primary Applications
Jaron Steel supplies 440C bars to high-end manufacturers for:
- Precision Bearings: Ball bearings and races for aerospace and industrial use.
- Cutting Tools: High-quality knives, surgical scalpels, and industrial blades.
- Valve Components: Valve seats, needle valves, and pump parts.
- Wear Parts: Bushings, nozzles, and structural parts in corrosive environments.
Quality Assurance by Jaron Steel
- Heat Treatment Support: We provide technical guidance on attaining the desired HRC levels.
- Precision Finishing: Available in h7 to h11 diameter tolerances.
- Full Traceability: Mill Test Certificates (MTC) according to EN 10204 3.1.
Technical Data & Composition
| Product Name | 440C Stainless Steel Bar | |
| Type | Steel Bar | |
| Outer Diameter | Round Bar | 4mm-500mm |
| Hexagon Bar | 18mm-57mm (11/16″ to 2-3/4″) | |
| Square Bar | 18mm-47mm (11/16″ to 1-3/4″) | |
| Flat Steel | 1/2 “to 10”, Thickness: 2mm-150mm, Can provide customized | |
| Length | 1-6 meters, Length can be customized | |
| Standard | ASTM, AISI, JIS, GB, DIN, EN, etc. | |
| Surface | Black, Bright Polished, Rough Turning, Mattness Surface Treatment, No. 4. BA, etc. | |
| Scope of Application | Stainless steel bars are used in a variety of industries such as shipbuilding,Defense, Automotive, Textiles, Paper and pulp, Manufacturing, Cement,Heavy earthmoving equipment and construction, etc. | |
Chemical Composition
| Element | Content (%) | Physical Property | Value |
| Carbon (C) | 0.95%−1.20% | Hardness (Annealed) | ≤269 HB |
| Chromium (Cr) | 16.0%−18.0% | Hardness (Hardened) | 58−60 HRC |
| Manganese (Mn) | ≤1.0% | Tensile Strength | ≥750 MPa |
| Molybdenum (Mo) | ≤0.75% | Yield Strength | ≥450 MPa |
Mechanical Properties
These values apply to AISI 440C in the hardened and tempered condition ($190^\circ\text{C}$ oil quench & temper).
| Property | Value (Metric) | Value (Imperial) |
| Tensile Strength | ≥1900 MPa | ≥275 ksi |
| Yield Strength (@ 0.2% offset) | ≥1280 MPa | ≥185 ksi |
| Hardness (Rockwell C) | 58−60 HRC | 58−60 HRC |
| Elongation (in 50mm) | 2%−5% | 2%−5% |
| Reduction of Area | 10% | 10% |
| Impact Strength (Izod) | 2−5 J | 1.5−3.7 ft-lb |
Physical Performance
| Density(g/cm³) | Modulus of Elasticity(Gpa) | Coefficient of Thermal Expansion(10-6/°C) | Coefficient of Thermal Conductivity(W/m*K) | Resistivity(ΜΩ. cm) |
| 8.03 | 193 | 16.9 | 16.2 | 72 |
| No | China | Japan | America | Korea | Germany | India | Australia | Taiwan, China | |
| GB | JIS | ASTM | UNS | KS | DIN | BIS | AS | CNS | |
| Austenitic Stainless Steel | |||||||||
| 1 | 12Cr17Mn6Ni5N | SUS201 | 201 | S20100 | STS201 | 1.4372 | 10Cr17Mn6Ni4N20 | 201-2 | 201 |
| 2 | 12Cr18Mn9Ni5N | SUS202 | 202 | S20200 | STS202 | 1.4373 | – | – | 202 |
| 3 | 12Cr17Ni7 | SUS301 | 301 | S20200 | STS301 | 1.4319 | 10Cr17Ni7 | 301 | 301 |
| 4 | 06Cr19Ni10 | SUS304 | 304 | S30400 | STS304 | 1.4301 | 07Cr18Ni9 | 304 | 304 |
| 5 | 022Cr19Ni10 | SUS304L | 304L | S30403 | STS304L | 1.4306 | 02Cr18Ni11 | 304L | 304L |
| 6 | 06Cr19Ni10N | SUS304N1 | 304N | S30451 | STS304N1 | 1.4315 | – | 304N1 | 304N1 |
| 7 | 06Cr19Ni9NbN | SUS304N2 | XM21 | S30452 | STS304N2 | – | – | 304N2 | 304N2 |
| 8 | 022Cr19Ni10N | SUS304LN | 304LN | S30453 | STS304LN | – | – | 304LN | 304LN |
| 9 | 10Cr18Ni12 | SUS305 | 305 | S30500 | STS305 | 1.4303 | – | 305 | 305 |
| 10 | 06Cr23Ni13 | SUS309S | 309S | S30908 | STS309S | 1.4833 | – | 309S | 309S |
| 11 | 06Cr25Ni20 | SUS310S | 310S | S31008 | STS310S | 1.4845 | – | 310S | 310S |
| 12 | 06Cr17Ni12Mo2 | SUS316 | 316 | S31600 | STS316 | 1.4401 | 04Cr17Ni12Mo2 | 316 | 316 |
| 13 | 06Cr17Ni12Mo2Ti | SUS316Ti | 316Ti | S31635 | – | 1.4571 | 04Cr17Ni12MoTi20 | 316Ti | 316Ti |
| 14 | 022Cr17Ni12Mo2 | SUS316L | 316L | S31603 | STS316L | 1.4404 | ~02Cr17Ni12Mo2 | 316L | 316L |
| 15 | 06Cr17Ni12Mo2N | SUS316N | 316N | S31651 | STS316N | – | – | 316N | 316N |
| 16 | 022Cr17Ni13Mo2N | SUS316LN | 316LN | S31653 | STS316LN | 1.4429 | – | 316LN | 316LN |
| 17 | 06Cr18Ni12Mo2Cu2 | SUS316J1 | – | – | STS316J1 | – | – | 316J1 | 316J1 |
| 18 | 022Cr18Ni14Mo2Cu2 | SUS316J1L | – | – | STS316J1L | – | – | – | 316J1L |
| 19 | 06Cr19Ni13Mo3 | SUS317 | 317 | S31700 | STS317 | – | – | 317 | 317 |
| 20 | 022Cr19Ni13Mo3 | SUS317L | 317L | S31703 | STS317L | 1.4438 | – | 317L | 317L |
| 21 | 06Cr18Ni11Ti S | SUS321 | 321 | S32100 | STS321 | 1.4541 | 04Cr18Ni10Ti20 | 321 | 321 |
| 22 | 06Cr18Ni11Nb | SUS347 | 347 | S34700 | STS347 | 1.4550 | 04Cr18Ni10Nb40 | 347 | 347 |
| Duplex Stainless Steel | |||||||||
| 1 | – | SUS329J1 | 329 | S32900 | STS329J1 | 1.4477 | – | 329J1 | – |
| 2 | 022Cr23Ni5Mo3N | – | S32205 | F60 | – | 1.4462 | – | 2205 | 2205 |
| 3 | 022Cr25Ni7Mo4N | – | S32750 | F53 | – | 1.4410 | – | 2507 | 2507 |
| Ferrite stainless steel | |||||||||
| 1 | 06Crl3Al | SUS405 | 405 | S40500 | STS405 | 1.4002 | 04Cr13 | 405 | 405 |
| 2 | 022Cr11Ti | SUH409 | 409 | S40900 | STS409 | 1.4512 | – | 409L | 409L |
| 3 | 022Cr12 | SUS410L | – | – | STS410L | – | – | 410L | 410L |
| 4 | 10Cr17 | SUS430 | 430 | S43000 | STS430 | 1.4016 | 05Cr17 | 430 | 430 |
| 5 | 10Cr17Mo | SUS434 | 434 | S43400 | STS434 | 1.4113 | – | 434 | 434 |
| 6 | 022Cr18NbTi | – | – | S43940 | – | 1.4509 | – | 439 | 439 |
| 7 | 019Cr19Mo2NbTi | SUS444 | 444 | S44400 | STS444 | 1.4521 | – | 444 | 444 |
| Martensitic Stainless Steel | |||||||||
| 1 | 12Cr12 | SUS403 | 403 | S40300 | STS403 | – | – | 403 | 403 |
| 2 | 12Cr13 | SUS410 | 410 | S41000 | STS410 | 1.4006 | 12Cr13 | 410 | 410 |
| 3 | 20Cr13 | SUS420J1 | 410 | S42000 | STS420J1 | 1.4021 | 20Cr13 | 420 | 420J1 |
| 4 | 30Cr13 | SUS420J2 | – | – | STS420J2 | 1.4028 | 30 Cr13 | 420J2 | 420J2 |
| 5 | 68Cr17 | SUS440A | 440A | S44002 | STS440A | – | – | 440A | 440A |
