· KAIPU Engineering · materials-encyclopedia · 1 min read
AISI A2 Air-Hardening Cold-Work Tool Steel
Materials encyclopedia entry for A2.
AISI A2 Air-Hardening Cold-Work Tool Steel is a reference entry for industrial cutting tools and blades. The composition, hardness, heat treatment and application guidance are summarised below for engineering reference.
Standard composition: C 0.95–1.05 %, Cr 4.75–5.50 %, Mo 0.90–1.40 %, V 0.15–0.50 %, Mn 0.40–1.00 %, Si 0.20–0.40 %, balance Fe
Hardness: Annealed HB 220–248; hardened HRC 57–62
Heat treatment: Austenitise 940–980 °C, air cool, double temper 175–540 °C
Properties: Good toughness (Charpy 28–40 J, ~2× D2). Air-hardening with low distortion. Lower wear resistance than D2 because of the lower Cr and V. Excellent machinability in the annealed state.
Applications: Slitter blades on tough paper, plastic film and rubber; shear blades on thick mild steel plate; precision blanking and forming dies; gauges and measuring tools.
Cross-reference: ≈ JIS SKD12, DIN 1.2363, GB Cr5Mo1V, BS BA2.
See also: D2 vs SKD11 comparison, Material Grade Converter, The KAIPU 5-Factor Blade Selection Framework.