S2

Data verified

S2 is a water-hardening shock-resisting steel with high silicon and molybdenum but no chromium or tungsten. It delivers S-class toughness in small hand and pneumatic tools at the lowest alloy cost.

Hardness50–58 HRC (water quench, shallow)

AISIS2

CategoryTool Steel

Chemical composition

Element	Content (%)
C	0.40–0.55
Si	0.90–1.20
Mn	0.30–0.50
Mo	0.30–0.60

Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.

Properties

Delivery condition	Annealed
Hardness (hardened)	50–58 HRC (water quench, shallow)
Density	7.85 g/cm³

Heat treatment

Harden 840–900 °C water or brine; temper 180–430 °C. Shallow hardening — small sections only.

Equivalent grades

Standard	Designation
aisi	S2

Compare side by side: S2 vs S5 · S2 vs S7

Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.

Applications & Processing

Applications: Hand chisels, screwdriver bits, pneumatic chisels, nail sets, small punches.

Processing: Water quench limits it to small, simple shapes; quench cracking risk on intricate sections — use S5 or S7 there.

Need S2 from stock?

Steel.Wiki is sponsored by Shenzhen NewAsia Special Steel (Nasteel), a special-steel stockholder in Shenzhen stocking mold, tool and alloy steels with EN 10204 3.1 certification.

Ask for a quotation Visit Nasteel

Source: ASTM A681 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.