Aluminum Die Casting Mold Steels: Comprehensive Technical Comparison and Selection Guide
Introduction
Selecting the appropriate aluminum die casting mold steels is essential for achieving optimal mold performance, enhanced durability, and resistance to heat checking. In aluminum die casting, molds must withstand extreme thermal cycling, mechanical stress, and wear. This guide covers key aluminum die casting mold steels, focusing on popular grades like SKD61 / H13, DIN 1.2367, and DH31-EX, and compares their chemical composition, heat treatment, mechanical properties, and applications.
Common High-Temperature Aluminum Die Casting Mold Steels
| Steel Grade | Origin & Manufacturer | Heat Checking Resistance | Toughness & Hardenability | Typical Hardness (HRC) | Applications | Availability |
| SKD61 / H13 | Japan (JIS), Europe & USA (DIN, AISI) | Good | Good | 50–54 | General aluminum die casting molds | Widely available, large inventory |
| DIN 1.2367 | Germany (Buderus, Lucchini, etc.) | Excellent | High | 50–54 | Large, high-temperature die casting molds | Stable supply from European mills |
| DH31-EX | Japan (Daido Steel) | Superior | Excellent | 41–48 (as-machined) | Large, high-cycle molds | Direct supply from Japan |
Aluminum Die Casting Mold Steel Properties Comparison
| Steel Grade | Key Alloy Composition | Heat Treatment | Machinability | Wear Resistance | Heat Checking Resistance | Toughness |
| SKD61 / H13 | Cr-Mo-V alloy | Quenched & tempered | Good | Good | Good | Good |
| DIN 1.2367 | High Mo content, ESR refined | Quenched & tempered | Medium | High | Excellent | High |
| DH31-EX | Modified 1.2367, Mo & V content | Special heat treatment | Low | Very high | Superior | Excellent |
Mechanical and Structural Properties Overview
| Property | SKD61 / H13 | DIN 1.2367 | DH31-EX |
| Hardness (HRC) | 50–54 | 50–54 | 41–48 |
| Toughness | Good | High | Excellent |
| Heat Checking Resistance | Good | Excellent | Superior |
| Hardenability | Good | High | Excellent |
| Machinability | Good | Medium | Low |
Recommended Applications of Aluminum Die Casting Mold Steels
| Requirement | Recommended Grade | Notes |
| Small to medium molds | SKD61 / H13 | Stable performance, lowest cost |
| Large high-temperature molds | DIN 1.2367 | Superior heat checking resistance and extended mold life |
| Ultra-large, high-cycle molds | DH31-EX | Maximum resistance to heat checking and longest mold life |
Supply Conditions & Brand Overview
- SKD61 / H13: A globally standardized mold steel grade with broad availability and competitive pricing. Ideal for general aluminum die casting molds. Ensure material standards and heat treatment certifications are verified.
- DIN 1.2367: A high-performance European hot-work tool steel designed for large, high-temperature molds. Cost and lead time are higher than SKD61. Recommended to purchase from authorized distributors with ESR or VIM refined quality.
- DH31-EX: Proprietary high-end steel from Japan’s Daido Steel, tailored for extreme die casting conditions requiring maximum mold longevity. Requires direct ordering and strict adherence to heat treatment processes.
Procurement Recommendations (Cost: Low to High)
- SKD61 / H13 — Cost-effective, widely available.
- DIN 1.2367 — Mid-to-high cost, suitable for demanding high-temperature molds.
- DH31-EX — Premium cost, for ultra-high-cycle and severe thermal stress molds.
Summary & Final Recommendations
| Performance Level | Recommended Steel Grade | Application Notes |
| Lower | SKD61 / H13 | Cost-sensitive, general-purpose aluminum molds |
| Medium | DIN 1.2367 | Large molds with frequent high-temperature cycles |
| Highest | DH31-EX | Extreme heat, pressure, and cycle environments |
Steel Product Information
SKD61 / H13 / 1.2344 Steel Introduction
Performance and application information of H13 / 1.2344 / SKD61 steel.
https://songshunsteel.com/product/h13-12344-skd61-steel/
DIN 1.2367 Steel Applications and Properties
Performance and application information of 1.2367 steel.
https://qilusteelgroup.com/1-2367-tool-steel/
DH31-EX Steel Introduction
Performance and application information of DH31-EX steel.
https://www.daido.co.jp/en/common/pdf/pages/products/tool/dh31_ex.pdf