Steel S2 · temper · default condition
Steel S2 Annealed
Properties of the Annealed condition, compared with the other S2 tempers.
Standard stock condition (183–217 HB) for machining, forming and drilling before hardening.
What is S2 Annealed?
S2 Annealed is S2 in the Annealed temper — standard stock condition (183–217 HB) for machining, forming and drilling before hardening. S2 Annealed has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 56% of steel grades. Elongation at break is 20% and the elastic modulus is 207 GPa (30 Msi). S2 Annealed has a density of 7.79 g/cm³ (0.281 lb/in³), lighter than 90% of steel grades. It melts at 1,425°C (2,597 °F).
Limitations
- Difficult to weld — 15/100, worse than 91% of steel grades
- Poor heat conductor — 25.5 W/m·K (14.7 BTU/hr·ft·°F), worse than 87% of steel grades
- Low electrical conductivity — 5.5 % IACS, worse than 81% of steel grades
S2 Annealed properties
Typical room-temperature values for S2 Annealed — 12 properties are specific to this condition; the rest are grade-level values shared by every S2 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
S2 Annealed has a density of 7.79 g/cm³ (0.281 lb/in³), lighter than 90% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
S2 Annealed has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 56% of steel grades. Elongation at break is 20% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
S2 Annealed is rated for continuous service to 400°C (752 °F). It conducts heat at 25.5 W/m·K (14.7 BTU/hr·ft·°F), worse than 87% of steel grades. Thermal expansion is 12.5 µm/m·K (6.94 µin/in·°F).
Electrical3
S2 Annealed conducts electricity at 5.5 % IACS, worse than 81% of steel grades.
Chemical & Environmental2
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of S2 Annealed takes about 34 MJ of energy and emits 2.4 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 45%.
Manufacturability8
S2 Annealed's machinability is fair (45/100, worse than 65% of steel grades); weldability poor (15/100); formability fair (35/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other S2 tempers and conditions
S2 is also supplied in 5 other conditions. The full side-by-side table is on the S2 overview.
- AnnealedDefaultStandard stock condition (183–217 HB) for machining, forming and drilling before hardening.460 MPa yield · 200 HB
- Hardened & TemperedMaximum-hardness condition for screwdriver bits and punch tips where wear beats toughness.1,900 MPa yield · 59 HRC
- Q&TGeneral hardened-and-tempered service condition (typically 54–58 HRC) for shock tools and bits.1,700 MPa yield · 57 HRC
- H&T 50-54 HRCToughest practical working condition for chisels, rivet sets and pneumatic-hammer tooling under heavy shock.1,500 MPa yield · 52 HRC
Working with S2 Annealed
Is S2 easy to machine?
Machine in the annealed condition with sharp carbide or cobalt HSS at moderate speed; the ~1 % Si makes chips gummy, so use generous coolant and finish-grind after hardening.
Can S2 be welded?
Not a welding grade — repair only, with 200–320 °C preheat, matching or austenitic filler, and an immediate re-temper to avoid quench cracks.
Can S2 be formed, bent or molded?
Forge 1010–1150 °C, never below ~900 °C, slow cool then anneal 760–790 °C; harden 845–885 °C with a severe water/brine quench (thin sections may be oil-quenched) and temper 175–370 °C for 50–60 HRC.
What surface finishes work on S2?
Grind, then protect with black oxide, manganese phosphate or oil; thin electroplating requires post-plate bake (~190 °C) to avoid hydrogen embrittlement.
S2 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C | 0.4 – 0.55 | 0.5 |
| Siraises hardenability and tempering resistance | 0.9 – 1.2 | 1.05 |
| Mn | 0.3 – 0.5 | 0.4 |
| Mo | 0.3 – 0.6 | 0.45 |
| Voptional grain refiner | ≤ 0.5 | 0.2 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
S2 Annealed — frequently asked
What is S2 Annealed used for?
S2 Annealed is typically used for screwdrivers, pneumatic tool bits and chisels. In short: tough; water-hardening tool.
What is the yield strength of S2 Annealed?
S2 Annealed has a typical yield strength of 460 MPa (66.7 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 56% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is S2 Annealed easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machine in the annealed condition with sharp carbide or cobalt HSS at moderate speed; the ~1 % Si makes chips gummy, so use generous coolant and finish-grind after hardening.
Can S2 Annealed be welded?
Not readily — weldability is rated poor (15/100). Not a welding grade — repair only, with 200–320 °C preheat, matching or austenitic filler, and an immediate re-temper to avoid quench cracks.
What surface finishes work on S2 Annealed?
Grind, then protect with black oxide, manganese phosphate or oil; thin electroplating requires post-plate bake (~190 °C) to avoid hydrogen embrittlement.
Can S2 Annealed be formed, bent or molded?
Forge 1010–1150 °C, never below ~900 °C, slow cool then anneal 760–790 °C; harden 845–885 °C with a severe water/brine quench (thin sections may be oil-quenched) and temper 175–370 °C for 50–60 HRC.
What is the maximum service temperature of S2 Annealed?
S2 Annealed is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in S2 Annealed?
Yes — S2 Annealed is available for CNC machining with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A681 — Standard Specification for Tool Steels Alloy — ASTM International (2022)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (tool steels) — ASM International (1990)
- Tool Steels, 5th Edition (Roberts, Krauss, Kennedy) — ASM International (1998)
- Shock-resisting tool steel S2 data sheet — Tool-steel producers (Crucible/Böhler/Hudson-type datasheets) (2020)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.