SUS420J1 Stainless Steel: Versatile Martensitic Grade for Tools

Key Characteristics

Martensitic Structure: Can be hardened by heat treatment, increasing its strength and hardness significantly.

High Chromium: Contains at least 12% chromium for good corrosion resistance, especially when polished.

Good Machinability (Annealed): More flexible and easier to machine in its soft, annealed state.

Magnetic: Like other martensitic steels, it possesses magnetic properties.

Performance

Hardness: Achieves high hardness (around 50 HRC) after hardening, ideal for cutting edges and wear surfaces.

Corrosion Resistance: Best in hardened and polished conditions; not ideal in the annealed state or for harsh chemical environments.

Heat Treatment: Quenching and tempering are crucial; avoid tempering between 425°C and 600°C.

Common Applications

Cutlery & Knives: Kitchen knives, pocket knives, and blades.

Medical & Dental Tools: Surgical instruments, dental picks.

Industrial Components: Gears, valves, shafts, and automotive parts.

Decorative Items: Where a polished finish and durability are needed.

In essence, SUS420J1 offers a practical blend of stainless properties and tool-grade hardness, making it a go-to choice for many demanding applications where both performance and appearance matter.