Steel 1050 Spheroidized
Heat-treated state
AISI/SAE 1050 · UNS G10500 · EN C50 · JIS S50C
Use for cold forging, heading, deep drawing or thread rolling of 0.5 % C steel.
Values for the Spheroidized condition
Other 1050 tempers and conditions
1050 is listed in 14 conditions; see the grade overview at 1050.
Compare all 14 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SpheroidizedThis page Spheroidize annealed (≈700 °C sub-critical, spheroidal carbides) | Use for cold forging, heading, deep drawing or thread rolling of 0.5 % C steel. | 330 | 560 | 28 | 163 HB | 10.7 % IACS |
HRDefault Hot rolled | Default stock condition for 50#/S50C bar and plate that will be machined and then quench- or induction-hardened. | 340 | 620 | 15 | 179 HB | — |
full anneal ≈790 °C, furnace cooled | Pick for maximum machinability/formability before hardening, or for stress-free blanks. | 365 | 636 | 24 | 187 HB | — |
Normalized | Uniform fine pearlitic structure — best base condition for plate, forgings and pre-machining stability. | 427 | 748 | 20 | 217 HB | — |
Q&T | Softest quench-and-temper option — maximum toughness and machinability with moderate strength. | 538 | 724 | 28 | 20 HRC | — |
Strain hardened and partially annealed, half hard | Cold-worked then sub-critically back-annealed 1050 strip: keeps most of the half-hard strength but recovers useful bend and forming ductility for parts that must still be shaped after rolling. | 580 | 720 | 12 | 17 HRC | 10.4 % IACS |
Cold drawn | Choose for straight, close-tolerance shafting with a better surface and higher yield than hot rolled. | 580 | 690 | 10 | 197 HB | — |
Induction hardened | Pick for shafts, gear teeth and guide rails needing a 55–60 HRC wear skin on a tough core. | 620 | 860 | 15 | 58 HRC | 9.6 % IACS |
Q&T | Use the water-quenched, 540 °C tempered condition at 26–30 HRC for shafts and couplings needing 862 MPa tensile with good toughness while remaining machinable. | 655 | 862 | 23 | 27 HRC | — |
Strain hardened, half hard | Cold-rolled / cold-drawn half-hard 1050 strip and bar: strain hardening raises yield and hardness to roughly twice the hot-rolled level while cutting cold ductility and impact toughness to a minimum. | 660 | 760 | 8 | 21 HRC | 10.3 % IACS |
Q&T | Balanced strength/toughness for shafts, gears and highly loaded machine parts. | 717 | 1,000 | 19 | 40 HRC | — |
Q&T | High-strength wear condition with slightly better ductility than the 205 °C temper. | 793 | 1,090 | 13 | 45 HRC | — |
Cold rolled hard strip | Strip condition for flat springs, shims and saw blanks that are formed then stress-relieved. | 800 | 900 | 4 | 27 HRC | 10.3 % IACS |
Q&T | Maximum hardness and wear resistance for small sections (blades, wear plates); low toughness. | 807 | 1,120 | 9 | 51 HRC | — |
What is 1050 Spheroidized?
1050 Spheroidized is 1050 heat treated to Spheroidized — use for cold forging, heading, deep drawing or thread rolling of 0.5 % C steel. 1050 Spheroidized has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 78% of steel grades. Elongation at break is 28% and the elastic modulus is 205 GPa (29.7 Msi). 1050 Spheroidized has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). HR is the default condition FabDigit quotes; Spheroidized is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- High electrical conductivity — 10.7 % IACS, better than 91% of steel grades
- Ductile — tolerates forming and impact — 28%, better than 89% of steel grades
- Conducts heat well — 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades
Limitations
- Low strength — 330 MPa (47.9 ksi), worse than 78% of steel grades
- Low fracture toughness — 65 MPa·√m (59.2 ksi·√in), worse than 75% of steel grades
1050 Spheroidized properties
Typical room-temperature values for 1050 Spheroidized; 22 are specific to this condition. Other listed values are 1050 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
1050 Spheroidized has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical14
1050 Spheroidized has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 78% of steel grades. Elongation at break is 28% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1050 Spheroidized is rated for continuous service to 400°C (752 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
1050 Spheroidized conducts electricity at 10.7 % IACS, better than 91% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 1050 Spheroidized takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability6
1050 Spheroidized's machinability is good (55/100, better than 62% of steel grades); weldability fair (35/100); formability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1050 Spheroidized
Is 1050 easy to machine?
Machine in the annealed or ≤30 HRC tempered state with carbide tooling and rigid setups; expect ~50 % of 1212 speeds and use chip breakers as it is not free-cutting.
Can 1050 be welded?
Poor weldability at 0.5 % C — preheat 200–300 °C, low-hydrogen consumables, control interpass and post-weld temper/stress-relieve to avoid HAZ cracking.
Can 1050 be formed, bent or molded?
Cold form only in annealed or spheroidized condition with generous bend radii (≥2t); hot forge 1100–1200 °C and normalize afterwards.
What surface finishes work on 1050?
No inherent corrosion resistance — oil, phosphate, black oxide, zinc or hard chrome plate; hardened surfaces grind and polish well for die and shaft applications.
1050 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 |
|---|---|---|
| CJIS S50C: 0.47–0.53 | 0.48 – 0.55 | 0.5 |
| Mn | 0.6 – 0.9 | 0.75 |
| SiNot specified in SAE 1050 (silicon-killed practice); required by JIS S50C / DIN C50 | 0.15 – 0.35 | 0.25 |
| P0.030 max for S50C / C50 | ≤ 0.04 | — |
| S0.035 max for S50C / C50 | ≤ 0.05 | — |
| CrResidual limit (JIS/DIN) | ≤ 0.2 | — |
| NiResidual limit | ≤ 0.2 | — |
| CuResidual limit | ≤ 0.3 | — |
| Fe | balance | — |
1050 Spheroidized — frequently asked
What is 1050 Spheroidized used for?
1050 Spheroidized is typically used for forged gears, shafts and hand tools. In short: hard; high-carbon spring steel.
What is the yield strength of 1050 Spheroidized?
1050 Spheroidized has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 78% of steel grades. Strength varies by condition: see the 14 listed tempers.
Is 1050 Spheroidized easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machine in the annealed or ≤30 HRC tempered state with carbide tooling and rigid setups; expect ~50 % of 1212 speeds and use chip breakers as it is not free-cutting.
Can 1050 Spheroidized be welded?
With care — weldability is rated fair (35/100). Poor weldability at 0.5 % C — preheat 200–300 °C, low-hydrogen consumables, control interpass and post-weld temper/stress-relieve to avoid HAZ cracking.
What surface finishes work on 1050 Spheroidized?
No inherent corrosion resistance — oil, phosphate, black oxide, zinc or hard chrome plate; hardened surfaces grind and polish well for die and shaft applications.
Can 1050 Spheroidized be formed, bent or molded?
Cold form only in annealed or spheroidized condition with generous bend radii (≥2t); hot forge 1100–1200 °C and normalize afterwards.
What is the maximum service temperature of 1050 Spheroidized?
1050 Spheroidized 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.
What is the difference between 1050-HR and 1050 QT-205?
HR is the default condition — default stock condition for 50#/S50C bar and plate that will be machined and then quench- or induction-hardened. QT-205: maximum hardness and wear resistance for small sections (blades, wear plates); low toughness. Yield strength is 340 MPa in HR versus 807 MPa in QT-205.
Can FabDigit make parts in 1050 Spheroidized?
Yes — 1050 Spheroidized is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- SAE J403 — Chemical Compositions of SAE Carbon Steels — SAE International (2014)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM (2020)
- JIS G4051 — Carbon steels for machine structural use (S50C) — JSA (2016)
- EN 10083-2 / DIN C50 (1.0540) — CEN (2006)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Machinery's Handbook (machinability ratings) — Industrial Press (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.