Steel High Carbon Steel · supply condition
Steel High Carbon Steel Spring Temper
Properties of the Spring Temper condition, compared with the other High Carbon Steel tempers.
Hardened-and-tempered strip supplied ready-to-form for flat springs, clips and shim stock.
What is High Carbon Steel Spring Temper?
High Carbon Steel Spring Temper is High Carbon Steel supplied in the Spring Temper condition — hardened-and-tempered strip supplied ready-to-form for flat springs, clips and shim stock. High Carbon Steel Spring Temper has a yield strength of 1,450 MPa (210 ksi) and a tensile strength of 1,650 MPa (239 ksi) — stronger than 97% of steel grades. Elongation at break is 4% and the elastic modulus is 205 GPa (29.7 Msi). High Carbon Steel Spring Temper has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). HR is the default condition FabDigit quotes; Spring Temper is available on request or by drawing note.
Advantages
- High strength — 1,450 MPa (210 ksi), better than 97% of steel grades
- Polishes to a fine finish — 70/100, better than 87% of steel grades
- High electrical conductivity — 9.6 % IACS, better than 77% of steel grades
Limitations
- Limited ductility — 4%, worse than 98% of steel grades
- Difficult to machine — 18/100, worse than 98% of steel grades
- Low fracture toughness — 35 MPa·√m (31.9 ksi·√in), worse than 95% of steel grades
- Limited formability — 15/100, worse than 87% of steel grades
- Limited service temperature — 250°C (482 °F), worse than 85% of steel grades
High Carbon Steel Spring Temper properties
Typical room-temperature values for High Carbon Steel Spring Temper — 9 properties are specific to this condition; the rest are grade-level values shared by every High Carbon Steel temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
High Carbon Steel Spring Temper has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical15
High Carbon Steel Spring Temper has a yield strength of 1,450 MPa (210 ksi) and a tensile strength of 1,650 MPa (239 ksi) — stronger than 97% of steel grades. Elongation at break is 4% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
High Carbon Steel Spring Temper is rated for continuous service to 250°C (482 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), better than 75% of steel grades. Thermal expansion is 11.4 µm/m·K (6.33 µin/in·°F).
Electrical3
High Carbon Steel Spring Temper conducts electricity at 9.6 % IACS, better than 77% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (9/100), worse than 98% of steel grades.
Sustainability4
Producing a kilogram of High Carbon Steel Spring Temper takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
High Carbon Steel Spring Temper's machinability is poor (18/100, worse than 98% of steel grades); weldability poor (25/100); formability poor (15/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other High Carbon Steel tempers and conditions
High Carbon Steel is also supplied in 9 other conditions. The full side-by-side table is on the High Carbon Steel overview.
- HRDefaultCheapest stock form for bar, plate and coil that will be machined and then heat treated.470 MPa yield · 24 HRC
- Patented HD WirePatented and heavily cold-drawn high-carbon wire (ASTM A227/A228, GB/T 4357) for coil springs; strength rises as diameter falls.1,800 MPa yield · 48 HRC
- H&T 58-62HRCFull hardening with 150–220 °C temper for knife edges, punches, springs washers and wear parts; brittle and notch sensitive.1,750 MPa yield · 60 HRC
- Spring TemperHardened-and-tempered strip supplied ready-to-form for flat springs, clips and shim stock.1,450 MPa yield · 48 HRC
- Q&TOil/water quench plus medium temper (400–540 °C) for high-strength shafts, dies and tools with usable toughness.950 MPa yield · 37 HRC
- CRStrip and sheet with tight thickness tolerance and bright surface, work-hardened and stronger but less ductile.760 MPa yield · 30 HRC
- CDCold-drawn round/flat bar for shafts and pins needing better straightness, finish and strength than hot rolled.720 MPa yield · 270 HB
- NormalizedAir-cooled fine pearlite for uniform structure and higher strength before final machining or hardening.520 MPa yield · 31 HRC
- AnnealedSoftest supply condition — pick for deep machining, bending or forming before hardening.380 MPa yield · 180 HB
- SpheroidizedBest machinability and cold-heading formability for 0.8–1.0 % C stock; spheroidal carbides in ferrite.350 MPa yield · 170 HB
Working with High Carbon Steel Spring Temper
Is High Carbon Steel easy to machine?
Machine in the annealed or spheroidized condition with sharp carbide or coated-carbide tools and rich coolant; above ~40 HRC switch to grinding, CBN or EDM.
Can High Carbon Steel be welded?
Poor weldability — preheat 200–300 °C, use low-hydrogen consumables, keep interpass heat and post-weld temper/stress-relieve immediately to avoid martensitic cracking.
Can High Carbon Steel be formed, bent or molded?
Cold form only when annealed/spheroidized and use generous bend radii; hot forge 1100–850 °C with slow cooling, then normalize or anneal before hardening.
What surface finishes work on High Carbon Steel?
Takes a fine polish when hardened but rusts fast — protect with black oxide, phosphate + oil, zinc or nickel plating, or paint; avoid hydrogen-embrittling acid pickles on hardened parts.
High Carbon Steel 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 |
|---|---|---|
| Cdefines the class; 1060≈0.60, 1080≈0.80, 1095≈0.95 %C | 0.55 – 1 | 0.8 |
| Mnup to 1.2 % in 65Mn/1566-type grades | 0.3 – 0.9 | 0.75 |
| Siresidual/deoxidiser | 0.1 – 0.35 | 0.25 |
| P | ≤ 0.04 | 0.02 |
| Smax; 0.08–0.13 in resulfurised free-machining variants | ≤ 0.05 | 0.02 |
| Curesidual | ≤ 0.25 | 0.1 |
| Fe | balance | — |
High Carbon Steel Spring Temper — frequently asked
What is High Carbon Steel Spring Temper used for?
High Carbon Steel Spring Temper is typically used for coil and leaf springs, cold-work blanks, saw blades and cutting blades, hand tools, wear plates and liners and hard-drawn spring wire. In short: high-carbon plate stock.
What is the yield strength of High Carbon Steel Spring Temper?
High Carbon Steel Spring Temper has a typical yield strength of 1,450 MPa (210 ksi) and a tensile strength of 1,650 MPa (239 ksi) — stronger than 97% of steel grades. Strength varies by condition: see the 10 listed tempers.
Is High Carbon Steel Spring Temper easy to machine?
Not especially — machinability is rated poor (18/100, worse than 98% of steel grades). Machine in the annealed or spheroidized condition with sharp carbide or coated-carbide tools and rich coolant; above ~40 HRC switch to grinding, CBN or EDM.
Can High Carbon Steel Spring Temper be welded?
Not readily — weldability is rated poor (25/100). Poor weldability — preheat 200–300 °C, use low-hydrogen consumables, keep interpass heat and post-weld temper/stress-relieve immediately to avoid martensitic cracking.
What surface finishes work on High Carbon Steel Spring Temper?
Takes a fine polish when hardened but rusts fast — protect with black oxide, phosphate + oil, zinc or nickel plating, or paint; avoid hydrogen-embrittling acid pickles on hardened parts.
Can High Carbon Steel Spring Temper be formed, bent or molded?
Cold form only when annealed/spheroidized and use generous bend radii; hot forge 1100–850 °C with slow cooling, then normalize or anneal before hardening.
What is the maximum service temperature of High Carbon Steel Spring Temper?
High Carbon Steel Spring Temper is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between High Carbon Steel-HR and High Carbon Steel-CR?
HR is the default condition — cheapest stock form for bar, plate and coil that will be machined and then heat treated. CR: strip and sheet with tight thickness tolerance and bright surface, work-hardened and stronger but less ductile. Yield strength is 470 MPa in HR versus 760 MPa in CR.
Can FabDigit make parts in High Carbon Steel Spring Temper?
Yes — High Carbon Steel Spring Temper is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4A — Steel Heat Treating Fundamentals — ASM International (2013)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM (2020)
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- GB/T 699 — Quality Carbon Structural Steels — SAC (2015)
- ASTM A228 — Steel Wire, Music Spring Quality — ASTM (2019)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- Mysteel / SMM (2026)
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.