4. Good toughness

5. Uniform hardness across large mould blocks

6. Suitable for nitriding to improve hardness on the surface

Common Applications

1. Plastic moulds (medium-size)

2. Pressure die-casting tools (low pressure)

3. Tooling plates

4. Automotive moulds

5. Extrusion dies

In terms of heat treatment, although the grade is usually supplied pre-hardened, it can be nitrided to improve surface hardness up to 60–65 HRC while retaining a tough and ductile core.

This results in high wear resistance, better surface stability, and longer tool life. Nitriding also improves corrosion resistance, which is beneficial when moulds are used with corrosive plastics or in humid environments.

It also offers good weldability, making it easier to repair moulds or modify them during maintenance. Proper welding procedures must be followed to avoid cracks or hardness variation, but overall the material performs reliably compared to other high-hardness tool steels.

Applications of 1.2311 include injection mould bases, blow moulds, die-casting tools for light alloys, machine parts, shafts, and other tooling components requiring moderate strength and high toughness. It performs exceptionally well for large moulds due to its uniform hardness distribution.

In conclusion, 1.2311 (P20 Tool Steel) is a balanced, cost-effective, and highly reliable tool steel grade. Its combination of machinability, toughness, polishability, and pre-hardened convenience makes it one of the most preferred materials for general-purpose mould manufacturing worldwide.