Tool Steel Selection by Application
Reference guide mapping tooling and machining applications to the tool steel groups commonly specified for them — cutting tools, hot forging, extrusion, cold-forming, shearing, die casting and molding, structural parts and battering tools.
| Application | High-speed tool steels (M, T) | Hot-work tool steels (H) | Cold-work tool steels (D, A, O) | Shock-resisting tool steels (S) | Mold steels (P) | Special-purpose tool steels (L) | Water-hardening tool steels (W) |
|---|---|---|---|---|---|---|---|
| Cutting tools Single-point types (lathe, planer, boring) Milling cutters Drills Reamers Taps Threading dies Form cutters | General-purpose production tools: M2, T1 For increased abrasion resistance: M3, M4, M10 Heavy-duty work calling for high hot hardness: T5, T15 Heavy-duty work calling for high abrasion resistance: M42, M44 | — | Tools with sharp edges (knives, razors) Tools for operations in which no high speed is involved, yet stability in heat treatment and substantial abrasion resistance are needed | Pipe cutter wheels | — | — | Uses that do not require hot hardness or high abrasion resistance. Examples with carbon content of applicable group: Taps (1.05-1.10% C) Reamers (1.10-1.15% C) Twist drills (1.20-1.25% C) Files (1.35-1.40% C) |
| Hot-forging tools and dies Dies and inserts Forging machine plungers and piercers | For combining hot hardness with high abrasion resistance: M2, T1 | Dies for presses and hammers: H20, H21 For severe conditions over extended service periods: H22-H26 | Hot trimming dies: D2 | Hot-trimming dies Blacksmith tools Hot-swaging dies | — | — | Smith tools (0.65-0.70% C) Hot chisels (0.70-0.75% C) Drop forging dies (0.90-1.00% C) Applications limited to short-run production |
| Hot extrusion tools and dies Extrusion dies and mandrels Dummy blocks Valve extrusion tools | Brass extrusion dies: T1 | Extrusion dies and dummy blocks: H21-H26 For tools that are exposed to less heat: H10-H14, H19 | — | Compression molding: S1 | — | — | — |
| Cold-forming dies Bending, forming, drawing, and deep-drawing dies and punches | Burnishing tools: M1, T1 | Cold-heading die castings: H13 | Drawing dies: O1 Coining tools: O1, D2 Forming and bending dies: A2 Thread rolling dies: D2 | Hobbing and short-run applications: S1, S7 Rivet sets and rivet busters | — | Blanking, forming, and trimmer dies when toughness has precedence over abrasion resistance: L6 | Cold-heading dies: W1 or W2 (C ~1.00%) Bending dies: W1 (C ~1.00%) |
| Shearing tools Dies for piercing, punching, and trimming Shear blades | Special dies for cold and hot work: T1 For work requiring high abrasion resistance: M2, M3 | For shearing knives: H11, H12 For severe hot-shearing applications: H21, H25 | Dies for medium runs: A2, A6, O1 Dies for long runs: D2, D3 Trimming dies (also for hot trimming): A2 | Cold and hot shear blades Hot punching and piercing tools Boilermaker tools | — | Knives for work requiring high toughness: L6 | Trimming dies (0.90-0.95% C) Cold-blanking and punching dies (1.00% C) |
| Die casting and molding dies | — | For aluminum and lead: H11, H13 For brass: H21 | A2, A6, O1 | — | Plastic molds: P2-P4, P20 | — | — |
| Structural parts for severe service conditions | Roller bearings for high-temperature environment: T1 Lathe centers: M2, T1 | For aircraft components (landing gears, arrester hooks, rocket cases): H11 | Lathe centers: D2, D3 Arbors: O1 Bushings A4 Gages: D2 | Pawls Clutch parts | — | Spindles and clutch parts (if high toughness is needed): L6 | Spring steel (1.10-1.15% C) |
| Battering tools, hand and power | — | — | — | Pneumatic chisels for cold work: S5 For higher performance: S7 | — | — | For intermittent use: W1 (0.80% C) |
- (a) Recommendations are shown as printed in the source guide; grade numbers are AISI designations.
Table notes
Cells list the tool steels commonly applied to each application, with the selection reason where the source gives one (for example, “For aluminum and lead: H11, H13”). An em dash means the source guide lists no recommendation for that group.
Source carbon figures for files read “1.35-40% C” (dropped decimal) and are shown as 1.35-1.40% C; minor typographic spacing has been normalized.
The guide covers typical practice — final grade choice also depends on part size, production volume, and heat-treatment capability. Confirm with your tooling engineer before ordering.
Related reference pages
How to select tool steels · Selection of tool steel for hot forging dies · Tool steels for hot forging, stamping and trimming dies · D2 tool steel · A2 tool steel · O1 tool steel · H13 tool steel · S7 tool steel · L6 tool steel · Tool steel properties chart · Tool steel machinability rating chart · Aluminum extrusion die steel selection
Source: ASM Handbook, Volume 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys, Table 4 “Reference guide for tool steel selection” (10th ed.). Reference data for comparison — confirm the final grade for your tooling with your supplier.