VR 400 is a premium-grade pre-hardened mould steel developed for high-performance applications in the plastic mould and tooling industry. It is considered an advanced improvement over standard P20, 1.2311, and 1.2738 grades. It is specially engineered to offer higher hardness (36–40 HRC) in the delivered condition, excellent toughness, and superior surface finish capabilities. This makes it suitable for demanding moulding applications where durability, strength, and surface quality are critical.

Key Properties of VR 400

1. Higher Pre-Hardened Strength (36–40 HRC)

Unlike standard P20 steels (30–34 HRC), its supplied at a higher, more stable hardness level. This results in improved mould life, wear resistance, and dimensional stability.

2. Excellent Hardness Uniformity

Its designed for large and extra-large mould blocks, providing uniform hardness across thick sections (up to 600 mm). This reduces the risk of internal soft spots or stress concentrations.

3. Superior Toughness

Despite its higher hardness, VR 400 maintains exceptional toughness. This reduces cracking during machining and mould operation, making it reliable for high-pressure injection moulding.

4. Outstanding Polishability & Surface Finish

The steel has a refined microstructure that allows:

a. High-gloss mirror polishing

b. Laser and chemical texturing

c. Scratch-free surface finishing

This makes VR 400 ideal for automotive and consumer product moulds requiring premium aesthetics.

5. Good Machinability

Even at 36–40 HRC, VR 400 machines surprisingly well. Tool wear is lower due to its balanced alloy composition and controlled manufacturing quality.

6. Suitable for Nitriding

VR 400 can be nitrided to achieve surface hardness 58–62 HRC, significantly improving wear resistance while preserving its tough core.

7.Weldability

Maintains good weldability for maintenance and modifications when using proper preheat and post-weld procedures.

Common Applications

1. Large and medium-size injection moulds

2. Blow moulds and PET moulds

3. High-performance mould bases

4. Automotive interior and exterior tooling

Home appliance moulds

6. Precision moulds requiring high polish or textured surfaces

Summary

VR 400 is a premium, high-hardness mould steel offering a powerful combination of toughness, polishability, uniform hardness, and long service life. It is ideal for manufacturers who require stronger and more durable mould steels than VR 300, P20, or 1.2311/1.2738. With its enhanced properties, VR 400 delivers excellent performance in demanding moulding conditions and high-end plastic component manufacturing.