AISI A6 Air-Hardening Cold-Work Tool Steel
AISI A6 — low-distortion air-hardening cold-work tool steel, HRC 58–60. Compare with A2 and D2 for blanking dies where dimensional stability matters.
AISI A6 (UNS T30106) is a low-distortion air-hardening cold-work tool steel with high Mn content (1.6–2.0 %) for austenite retention. Slightly tougher than A2 at equivalent hardness (HRC 58–60); used where A2 standard is acceptable but improved dimensional stability during hardening is critical — blanking dies, forming tools.
Standard composition: C 0.65–0.75 %, Cr 0.90–1.30 %, Mo 0.90–1.40 %, Mn 1.80–2.50 %, Si 0.20–0.40 %, balance Fe
Hardness: Annealed HB 217–248; hardened HRC 54–60
Heat treatment: Austenitise 830–870 °C, air cool, double temper 175–540 °C
Properties: High toughness from the lower carbon and higher Mn. Wear resistance lower than D2 (smaller carbide fraction). Deep-hardening with low distortion. Used for impact-loaded parts where D2 would chip.
Applications: Granulator rotor knives, shear blades on thick plate, crusher blades, blanking dies for thick mild steel, coining dies.
Cross-reference: ≈ DIN 1.2343 (close).
See also.
