Steel 1080-HR (Hot rolled)
Supply condition · default condition
AISI/SAE 1080 · UNS G10800 · GB 80
Cheapest stock form for blanks that will be machined and then hardened; pearlitic as-rolled structure.
Values for the HR condition
Other 1080 tempers and conditions
1080 is listed in 9 conditions; see the grade overview at 1080.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
spheroidize/full annealed (~790 °C, slow cool) | Softest, most machinable and most formable condition — pick it for heavy machining or cold forming before hardening. | 375 | 615 | 25 | 174 HB | — |
austenitized ~900 °C, air cooled | Uniform fine pearlite for consistent machining and predictable response to later hardening. | 524 | 1,010 | 11 | 31 HRC | — |
HRDefaultThis page Hot rolled | Cheapest stock form for blanks that will be machined and then hardened; pearlitic as-rolled structure. | 585 | 965 | 12 | 31 HRC | — |
Spheroidized Annealed + Cold Drawn | Spheroidize-annealed (globular carbides in ferrite) then cold drawn — moderate strength with the best cold formability and machinability attainable in 0.80 % C steel, the standard feed condition for cold-heading and pre-hardened spring parts. | 620 | 745 | 10 | 20 HRC | 9.6 % IACS |
Cold rolled | Thin strip for saw blades, shims, flat springs and stamped blades; tight thickness and good surface. | 830 | 1,000 | 8 | 32 HRC | 9.5 % IACS |
Cold drawn | Use when a bright, close-tolerance bar with higher yield strength is wanted straight from stock. | 855 | 1,015 | 10 | 31 HRC | — |
Quenched and tempered | Balanced strength/toughness condition for springs, chisels and highly loaded machine parts in thin sections. | 980 | 1,310 | 10 | 40 HRC | — |
Quenched and low-temperature tempered | Blade, cutter and wear-part condition: maximum hardness and edge retention, low impact toughness. | 1,500 | 1,800 | 5 | 52 HRC | — |
Patented cold-drawn wire (hard-drawn spring wire) | Patented (sorbitic) and heavily drawn wire for coil springs and wire forms — very high strength as-drawn, no further hardening needed. | 1,500 | 1,750 | 4 | 47 HRC | 9 % IACS |
What is 1080-HR?
1080-HR is 1080 supplied in the HR condition — cheapest stock form for blanks that will be machined and then hardened; pearlitic as-rolled structure. 1080-HR has a yield strength of 585 MPa (84.8 ksi) and a tensile strength of 965 MPa (140 ksi) — stronger than 75% of steel grades. Elongation at break is 12% and the elastic modulus is 205 GPa (29.7 Msi). 1080-HR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,385°C (2,525 °F).
Advantages
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
- Polishes to a fine finish — 65/100, better than 78% of steel grades
- High strength — 585 MPa (84.8 ksi), better than 75% of steel grades
- High electrical conductivity — 9.5 % IACS, better than 75% of steel grades
Limitations
- Limited ductility — 12%, worse than 84% of steel grades
- Difficult to machine — 35/100, worse than 84% of steel grades
- Difficult to weld — 20/100, worse than 84% of steel grades
1080-HR properties
Typical room-temperature values for 1080-HR; 11 are specific to this condition. Other listed values are 1080 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
1080-HR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,385°C (2,525 °F).
Mechanical15
1080-HR has a yield strength of 585 MPa (84.8 ksi) and a tensile strength of 965 MPa (140 ksi) — stronger than 75% of steel grades. Elongation at break is 12% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1080-HR is rated for continuous service to 400°C (752 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 11.3 µm/m·K (6.28 µin/in·°F).
Electrical3
1080-HR conducts electricity at 9.5 % IACS, better than 75% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 1080-HR takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
1080-HR's machinability is fair (35/100, worse than 84% of steel grades); weldability poor (20/100); formability poor (25/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1080-HR
Is 1080 easy to machine?
Machine in the annealed or normalized state with rigid setups, sharp carbide or coated carbide at moderate speed and good flood coolant; hardened 1080 needs grinding or ceramic/CBN tooling.
Can 1080 be welded?
Poor weldability — high carbon equivalent causes hard, crack-prone HAZ; if unavoidable use 200–300 °C preheat, low-hydrogen filler, slow cool and immediate stress relief/temper.
Can 1080 be formed, bent or molded?
Cold form only in the spheroidize-annealed condition and expect large springback; hot form at 950–1150 °C, then normalize before hardening.
What surface finishes work on 1080?
No corrosion resistance: finish with oil, black oxide, phosphate, zinc plating or paint; hardened surfaces take a fine polish and can be shot-peened for fatigue life.
1080 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 |
|---|---|---|
| CSAE J403/ASTM A29; GB 80 is 0.77–0.85 | 0.75 – 0.88 | 0.8 |
| MnGB 80 uses 0.17–0.37 Mn | 0.6 – 0.9 | 0.75 |
| Sitypical for killed hot-rolled product; not specified for all bar grades | 0.15 – 0.35 | 0.25 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.05 | 0.03 |
| Fe | balance |
1080-HR — frequently asked
What is 1080-HR used for?
1080-HR is typically used for flat and leaf springs, music and patented spring wire, mower and cutter blades, knife blanks, cold-work tool blanks and spiral and clock springs. In short: high-carbon spring bar.
What is the yield strength of 1080-HR?
1080-HR has a typical yield strength of 585 MPa (84.8 ksi) and a tensile strength of 965 MPa (140 ksi) — stronger than 75% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 1080-HR easy to machine?
Not especially — machinability is rated fair (35/100, worse than 84% of steel grades). Machine in the annealed or normalized state with rigid setups, sharp carbide or coated carbide at moderate speed and good flood coolant; hardened 1080 needs grinding or ceramic/CBN tooling.
Can 1080-HR be welded?
Not readily — weldability is rated poor (20/100). Poor weldability — high carbon equivalent causes hard, crack-prone HAZ; if unavoidable use 200–300 °C preheat, low-hydrogen filler, slow cool and immediate stress relief/temper.
What surface finishes work on 1080-HR?
No corrosion resistance: finish with oil, black oxide, phosphate, zinc plating or paint; hardened surfaces take a fine polish and can be shot-peened for fatigue life.
Can 1080-HR be formed, bent or molded?
Cold form only in the spheroidize-annealed condition and expect large springback; hot form at 950–1150 °C, then normalize before hardening.
What is the maximum service temperature of 1080-HR?
1080-HR 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 1080-HR and 1080-CD?
HR is the default condition — cheapest stock form for blanks that will be machined and then hardened; pearlitic as-rolled structure. CD: use when a bright, close-tolerance bar with higher yield strength is wanted straight from stock. Yield strength is 585 MPa in HR versus 855 MPa in CD.
Can FabDigit make parts in 1080-HR?
Yes — 1080-HR 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
- 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 (grade 80) — SAC (2015)
- ASTM A684/A684M — High-Carbon Steel Strip — ASTM (2021)
- ASTM A227/A229 — Hard-Drawn and Oil-Tempered Spring Wire — ASTM (2017)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.4 — Heat Treating; Vol.16 — Machining — ASM International (1991)
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.