What Material Is Used for Cold Heading Dies?

Selecting the right die material is one of the most impactful decisions in fastener manufacturing. The wrong choice leads to premature wear, dimensional drift and unplanned downtime. This guide covers the three main material families used in cold heading dies and how to match them to your application.

1. Tungsten Carbide (硬质合金)

Tungsten carbide is the premium choice for high-volume production. It offers the best wear resistance and dimensional stability among all die materials.

• Hardness: HRA 88–93 depending on cobalt content
• Best for: High-volume screw, bolt and nut production (100K+ hits)
• Cobalt content: Lower cobalt (6–10%) = harder and more wear-resistant; higher cobalt (12–15%) = better toughness for impact-heavy applications
• Cost: Highest initial cost, but lowest cost-per-part at volume

2. High-Speed Steel / HSS (高速钢)

HSS offers a balance between wear resistance and toughness. It’s the most versatile die material for mid-volume production.

• Hardness: HRC 62–68 after heat treatment
• Best for: Medium-volume production, complex geometries, and applications requiring regrinding
• Common grades: SKH51 (M2), SKH55 (M35), SKH59 (M42) for higher red hardness
• Advantage: Can be re-sharpened multiple times, extending die life

3. Powder Metallurgy Steel (粉末钢)

PM steels represent the next step between conventional HSS and carbide. They offer finer grain structure and more uniform carbide distribution.

• Hardness: HRC 64–70
• Best for: High-precision applications where carbide is too brittle and conventional HSS wears too fast
• Common grades: ASP-23, ASP-30, HAP-40, HAP-72
• Advantage: 2–3× the wear life of conventional HSS with better toughness

Quick Selection Guide

At BENC MOULD, we help customers select the optimal material based on their specific production parameters. Our standard recommendation: tungsten carbide for high-volume standard screws, HSS for low-volume and complex shapes, and PM steel when you need the best balance of both.