9Cr18 Martensitic Stainless Steel Round Bar High Hardness 440A Stainless Steel Rod

When an application demands a combination of high hardness, outstanding wear resistance, and good corrosion resistance, 9Cr18 martensitic stainless steel round bar is a proven choice. Equivalent to AISI 440C and DIN 1.4125, this high-carbon martensitic grade is a hardened stainless steel widely used for bearings, valves, cutlery, and precision mechanical components that must stay sharp, strong, and rust-resistant in service.

9Cr18 is a high-carbon, chromium-bearing martensitic stainless steel with a carbon content of approximately 0.90–1.00% and chromium of 17–19%. This chemistry allows the material to be through-hardened by heat treatment to reach a working hardness of roughly HRC 56–59, delivering excellent wear resistance and edge retention. The addition of molybdenum in 9Cr18Mo improves hardenability and corrosion resistance further. Supplied in the annealed condition for easy machining, the bar is subsequently hardened and tempered by the customer or by our heat-treatment service.

• High hardness after heat treatment, typically HRC 56–59
• Excellent wear resistance and edge retention for cutting and bearing duty
• Good corrosion resistance compared with plain carbon tool steels
• Fine, homogeneous structure for stable hardening response
• Good machinability in the annealed delivery condition

• Ball bearings, rollers, and bearing races
• Valve parts, nozzles, and pump components
• High-grade cutlery, blades, and cutting tools
• Measuring tools, gauges, and precision instruments
• Molds, dies, and wear-resistant machine parts

• Product form: hot-rolled, forged, or cold-drawn round bar
• Diameter range: 3 mm – 300 mm (custom sizes available)
• Length: 3000–6000 mm, or cut to order
• Surface: black, bright, peeled, turned, or polished
• Delivery condition: annealed (soft) or quenched & tempered
• Test certificate: EN 10204 3.1 / 3.2 mill test certificate

We supply 9Cr18 and 9Cr18Mo martensitic stainless steel round bars with strict chemistry and hardness control, full traceability, and mill test certificates. With a wide size range, flexible cutting, and reliable worldwide delivery, we support bearing, valve, cutlery, and precision engineering projects with consistent, high-performance material. Contact our team today for specifications, availability, and a competitive quotation.