Shock-resisting steel

Shock-resisting steels are a class of tool steels designed to resist breakage by shock. Under the AISI classification system there are seven types, labeled S1 to S7.

Overview

Shock-resisting steels are designed to have high impact resistance (toughness), along with other properties such as strength, hardness. Silicon is a common addition to this class of steels, as it provides tempering resistance and increases toughness.^[1]

Applications for shock-resisting steels includes springs, as well as chisels, dies for forging, and punches.^[1] S2 steel is also used to make ball bearings for the mining industry.^[2] They are also used for screwdrivers and driver bits.^[3]

Type	C %	Si %	V %	Cr %	Mn %	Ni %	Mo %	W %
S1 (UNS T41901)[1][3][a]	0.40–0.55	0.15–1.20	0.15–0.30	1.00–1.80	0.10–0.40	<0.30	<0.50	1.50–3.00
S2 (UNS T41902)[1][3]	0.40–0.55	0.90–1.20	<0.50	—	0.30–0.50	<0.30	0.30–0.60	—
S3[4]	0.50	2.00	—	0.74	—	—	—	1.00
S4 (UNS T41904)[1]	? ~0.4–0.65	1.75–2.25	0.35	0.35	0.60–0.90		—
S5 (UNS T41905)[1][3]	0.50–0.65	1.75–2.25	<0.35	<0.50	0.60–1.00	—	0.20–1.35	—
S6 (UNS T41906)[3]	0.40–0.50	2.00–2.50	0.20–0.40	1.20–1.50	1.20–1.50	—	0.30–0.50	—
S7 (UNS T41907)[1][3]	0.45–0.55	0.20–1.00	0.20–0.30[b]	3.00–3.50	0.20–0.90	—	1.30–1.80	—

1. Commonly known as "tungsten chisel steel".
2. May be omitted.

SVCM

"SVCM" redirects here. For the medical technique, see Spatial vectorcardiometry.

SVCM steel is a kind of shock-resisting steel.^[5] SVCM steel is an alloy of carbon, silicon, chromium, magnesium, nickel, molybdenum and lead.^[6] SVCM+ in addition is quenched and tempered achieving a high hardness (HRC 59).^[6] SCVM+ has better torsional properties than chromium-vanadium steel (Cr-V).^[7]