Steel selection by application — hot-work, warm-work, and the special cases

Powder-metallurgy hot-work steels are made by gas-atomizing molten tool steel and HIPing the powder to full density. The result is a tool steel with very fine, uniform carbide distribution (1-3 µm versus 10-30 µm in conventional H13) and no carbide segregation. Crucible CPM 1V is the relevant PM hot-form grade. It carries higher carbon and vanadium than H13, and reaches the low 60s HRC while keeping impact toughness in a range that conventional ingot-route steels cannot deliver at that hardness.

Where CPM 1V earns its place: hot-form punches that are failing by abrasive wear at H13's hardness ceiling, hot-trim die inserts on long-running production where edge retention is the failure mode, and warm-forging tooling where wear dominates and the temperature is below the regime where H13's secondary hardening is the differentiator. CPM 3V is the higher-toughness sibling for blanking dies and forging punches that need impact tolerance above what 1V offers.

Two corrections on PM grades that show up in vendor pitches. First, Uddeholm Caldie is a cold-work grade, not hot-work. It is excellent for AHSS blanking, cold forging, and machine knives. It does not belong in a hot-forge die specification. Use DIEVAR, QRO 90 Supreme, or W360 ISOBLOC for the hot-work premium tier. Second, Erasteel ASP 2030 is a Co-bearing PM high-speed steel for cutting tools, cold forging, and fine blanking. Erasteel itself does not position the ASP family for hot-forge dies. The right PM hot-form reference is Crucible CPM 1V, not ASP.