BS 4659

AISI O2 Steel is an oil hardening tool steel supplied in the annealed condition. ASTM O2 steel is widely used for universal use. It's similar to AISI O1 grade tool steel, with addition of Mo element.

AISI L6 Tool Steel is one of alloy, oil-hardening tool steel in ASTM A681 standard. Some equivalent steel is 1.2714, 55NiCrMoV7, SKT4, BH224/5 steel.

ASTM/AISI A2 tool steel is a versatile, air hardening chromium alloy tool steel that replaces O1 tool steel when safer hardening, less distortion and increased wear resistance are required.

AISI H12 steel is a 4.75~5.5% chromium, general-purpose hot work tool steel. ASTM/AISI H12 Steel is a deep-hardening, air-hardening steel that exhibits minimal size change during heat treatmnet.

AISI H11 tool steel is a 5% chromium hot work tool steel. H11 tool steels have the higher toughness, with some reduction in wear resistance and temper resistance.

H10 Tool Steel is one chromium hot-work tool steel that exhibits excellent resistance to softening at elevated temperature. H10 tool steel is recommended for difficult hot work tooling applications.

ASTM T5 Tool Steel is one of tungsten high-speed tool steel. It belongs to ASTM A600, together with T1, T2, T4 Tool Steel. All are in group T in ASTM A600