440B martensitic stainless steel is a high-performance stainless steel known for high hardness, good wear resistance, and reliable corrosion resistance. Also known as 9Cr18MoV and 1.4112, it is widely used for knife blades, scissors, cutting tools, surgical instruments, and precision parts.
Compared with ordinary stainless steels, 440B stainless steel offers a better balance of hardness, edge stability, and rust resistance. With proper heat treatment, it provides stable performance, long service life, and dependable cutting results.
It is a practical choice for kitchen knives, outdoor knives, grooming scissors, machining tools, and medical cutting instruments.
Medical and surgical instruments
Medical and surgical instruments
Precision mechanical components
| ZEICIN Grade | GB | ASTM | JIS | DIN |
| YTG188 | 9Cr18MoV | 440B | SUS440B Modify | 1.4112 |
| C | Cr | Mn | Si | Mo | V |
| 0.85~0.95 | 17.00~19.00 | ≤0.80 | ≤0.80 | 1.00~1.80 | 0.07~0.12 |
| Co | S | P | Ni | Nb | W |
| – | ≤0.03 | ≤0.035 | <0.60 | – | – |
Annealing softens the steel to approximately HB 269, helping relieve internal stress and improve machinability before further heat treatment.
The steel is heated to 1040–1080°C and then rapidly cooled. This process increases hardness and improves wear resistance.
Tempering is carried out at around 200°C to reduce residual stress and adjust the final hardness. After proper heat treatment, the final hardness can reach 55–57 HRC.
ZEICIN Steel provides 440B martensitic stainless steels in a wide range of product forms, including round bar, flat bar, square bar, and sheet. Available surface finishes include black, annealed, shot blasted, milled, peeled, centerless, and ground to meet different processing and application needs.
We offer stable quality, consistent mechanical performance, and dependable bulk supply. Customization is available for both size and chemical composition, allowing us to meet specific project and market requirements efficiently.
| Type | Specification (mm) | Surface Condition |
| Round Bar | 1-50 or Customized | Black / Centerless / Turned / Peeled |
| Flat Bar | (3-40)*(12-156)*(2000-5300) | Annerled, Shot-Blasted / Milled / Black |
| Square Bar | (6*6)-(180*180) | Annerled, Shot-Blasted / Milled / Black |
| Steel Plate | (0.6-12)*(500-1000)*(1000-3000) | Black / Sandblasted / Granding |
Different surface conditions affect appearance, dimensional accuracy, and machining allowance. The images below show common delivery options (actual products may vary by size and batch).
ZEICIN STEEL specializes in high-carbon martensitic stainless steels such as 440C. Our focus is on cleaner steel, uniform microstructure, stable heat treatment response, and improved corrosion resistance, ensuring longer service life and consistent batch performance.
Our R&D team participates in national-level research programs and key science and technology initiatives. With strong institutional support, we continuously advance the development of high-performance martensitic stainless steels, ensuring ongoing innovation and technical improvement.
We adopt an advanced melting route of EAF, LF, VD, and RS-ESR. This process improves steel cleanliness, refines carbide distribution, and enhances corrosion resistance and heat treatment stability, resulting in more reliable performance and longer service life.
We focus on the production and optimization of martensitic stainless steels such as 440C for knife blades, surgical instruments, and precision components. Our materials deliver stable hardness, excellent wear and corrosion resistance, and consistent edge performance in demanding applications.
Yes. We are a factory. ZEICIN STEEL produces high-quality, cost-effective special steels, including stainless steel, tool & die steel, and high-speed steel. We also have our own import/export license, so we can serve overseas customers directly and support stable supply with batch traceability.
Yes. For first-time cooperation, we can provide a limited quantity of samples for verification (such as grade confirmation, machining trials, or heat-treatment evaluation). Samples can be shipped by international courier, and the courier cost is paid by the buyer. We value honest cooperation and look forward to a long-term win-win partnership.
Our common international payment methods include T/T and L/C. For trade terms, we can also support options such as DDU based on the order. The final payment method and terms can be confirmed according to your country/region, order value, and delivery method.
Our products use standard industrial packaging to ensure safe transportation. If you need custom packaging, please let us know when placing your order.
If the products are in stock, delivery usually takes 5–7 days.
If the products are not in stock, delivery time is about 30–40 days, depending on the order quantity.
