Tool Steel Casting Alloys

Tool steels are a family of carbon and alloy steels specifically formulated for applications where hardness, wear resistance, and the ability to maintain a cutting edge under demanding conditions are essential. Tool steels are exceptionally hard, tough, or wear-resistant alloys whose properties come from both their chemistry and the subsequent heat treatments applied after casting. They are the material of choice for cutting tools, dies, punches, shear blades, and other tooling where standard carbon or alloy steels would quickly fail.

Tool Steel Grades

Engineered Precision Casting Company pours a range of tool steel alloys for investment casting, including A, D, H, and S series grades.

A Series — Air-Hardening Cold Work Tool Steel A-grade tool steels are air-cooled and offer excellent wear resistance, hardness, and dimensional stability at elevated temperatures. The high chromium content minimizes distortion during heat treatment, making them well suited for close-tolerance tooling. A2 is the most widely used grade and provides a cost-effective balance of wear resistance and toughness for a broad range of cold work applications including dies, shear blades, punches, and plastic molds.

Common grades: A2, A6, A7

D Series — High Carbon, High Chromium Cold Work Tool Steel D-grade tool steels contain significantly more carbon and nearly triple the chromium content of A-grade tool steel, enabling them to maintain their hardness at temperatures approaching 800°F. This makes them the highest wear-resistance option among cold work tool steels, ideal for drawing dies, blanking tools, and long-run production tooling subject to continuous abrasive contact. The trade-off is lower toughness compared to A and S series grades — D-series steels are best suited to low-impact, high-wear applications.

Common grades: D2, D3, D7

H Series — Hot Work Tool Steel H-series tool steels are specifically formulated for applications involving prolonged exposure to elevated temperatures. Hot work tool steels can operate at temperatures up to 1004°F (540°C) and are commonly used in dies, stamps, extruders, and compressors. Chromium-based H grades such as H11 and H13 are the most widely used, offering an excellent balance of heat resistance, toughness, and thermal fatigue resistance. They are the standard choice for hot forging dies, extrusion tooling, and high-temperature cutting applications.

Common grades: H11, H13, H21

S Series — Shock-Resisting Tool Steel S-grade tool steels have high impact resistance and low carbon content, allowing them to resist shock at both low and high temperatures. Silicon is the defining alloying element in this family, contributing to outstanding toughness without sacrificing too much hardness. S-series grades are the preferred choice for tooling subject to repeated impact loads, including chisels, punches, hammers, and stamping dies. S7 is the most commonly investment cast S-grade and is valued for its combination of air hardenability, machinability, and dimensional stability during heat treatment.

Common grades: S2, S5, S7

Contact Us to Learn More About Tool Steel Investment Casting Alloys

Contact us to discuss your tool steel casting project requirements and learn more about our investment casting solutions.