Steel 8630-CR (Cold rolled)
Supply condition
AISI/SAE 8630 · UNS G86300
Cold-rolled strip/sheet with tight thickness and smooth surface; higher strength but low ductility, usually stress-relieved before forming.
Values for the CR condition
Other 8630 tempers and conditions
8630 is listed in 8 conditions; see the grade overview at 8630.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Temper | Fully/spheroidize annealed (~845 °C, furnace cool) for maximum softness before heavy machining or cold forming. | 372 | 565 | 29 | 156 HB | — |
HRDefault Hot rolled | Mill hot-rolled bar/plate as most commonly stocked; buy when parts will be heat treated after machining. | 415 | 690 | 22 | 197 HB | — |
Heat Treat State | Normalized ~870 °C air cool: uniform fine grain and good toughness, typical pre-condition for forgings and weldments. | 430 | 650 | 23.5 | 187 HB | — |
sour service (NACE MR0175/ISO 15156) | High-temperature temper limiting hardness to 22 HRC max for H2S-containing (sour) subsea and wellhead components. | 585 | 790 | 22 | 20 HRC | — |
CRThis page Cold rolled | Cold-rolled strip/sheet with tight thickness and smooth surface; higher strength but low ductility, usually stress-relieved before forming. | 620 | 760 | 12 | 20 HRC | 8 % IACS |
Cold drawn | Cold-drawn bar for good size tolerance, straightness and improved machined finish without further heat treatment. | 655 | 760 | 15 | 223 HB | 44 W/m·K |
Quenched and tempered | Oil quenched from ~860 °C and tempered ~540–595 °C to about 28–32 HRC — the standard structural/oilfield condition balancing strength and toughness. | 860 | 1,000 | 18 | 30 HRC | — |
low-temperature temper, high strength | Tempered ~315–425 °C for high strength shafts, pins and fasteners where toughness demands are moderate. | 1,280 | 1,400 | 12 | 43 HRC | — |
What is 8630-CR?
8630-CR is 8630 supplied in the CR condition — cold-rolled strip/sheet with tight thickness and smooth surface; higher strength but low ductility, usually stress-relieved before forming. 8630-CR has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 78% of steel grades. Elongation at break is 12% and the elastic modulus is 205 GPa (29.7 Msi). 8630-CR 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; CR is available on request or by drawing note.
Advantages
- High strength — 620 MPa (89.9 ksi), better than 78% of steel grades
Limitations
- Limited ductility — 12%, worse than 84% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
8630-CR properties
Typical room-temperature values for 8630-CR; 23 are specific to this condition. Other listed values are 8630 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
8630-CR 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).
Mechanical13
8630-CR has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 78% of steel grades. Elongation at break is 12% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
8630-CR is rated for continuous service to 300°C (572 °F). It conducts heat at 43 W/m·K (24.8 BTU/hr·ft·°F), better than 51% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
8630-CR conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 8630-CR takes about 30 MJ of energy and emits 2.2 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 35%.
Manufacturability7
8630-CR's machinability is good (58/100, better than 75% of steel grades); weldability fair (38/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 8630-CR
Is 8630 easy to machine?
Machines best annealed or ~200 HB (about 65 % of AISI 1212); use rigid setups, carbide tooling and reduced speeds above 30 HRC.
Can 8630 be welded?
Weldable with low-hydrogen consumables but CE ≈0.75 demands 200–300 °C preheat, controlled interpass and PWHT/re-temper to avoid HAZ cracking.
Can 8630 be formed, bent or molded?
Hot forge 1100–1200 °C and normalize afterwards; cold forming only in the annealed condition with generous bend radii.
What surface finishes work on 8630?
No inherent corrosion resistance — protect by phosphating, zinc/Ni plating, thermal spray or paint; nitriding and induction hardening give good wear surfaces (avoid electroplating >32 HRC without bake-out).
8630 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 | 0.28 – 0.33 | 0.3 |
| Mn | 0.7 – 0.9 | 0.8 |
| Si | 0.15 – 0.35 | 0.25 |
| Ni | 0.4 – 0.7 | 0.55 |
| Cr | 0.4 – 0.6 | 0.5 |
| Mo | 0.15 – 0.25 | 0.2 |
| P | ≤ 0.04 | — |
| S | ≤ 0.04 | — |
| Fe | balance | — |
8630-CR — frequently asked
What is 8630-CR used for?
8630-CR is typically used for shafts, gears and fittings. In short: workhorse Cr-Mo bar.
What is the yield strength of 8630-CR?
8630-CR has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 78% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 8630-CR easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machines best annealed or ~200 HB (about 65 % of AISI 1212); use rigid setups, carbide tooling and reduced speeds above 30 HRC.
Can 8630-CR be welded?
With care — weldability is rated fair (38/100). Weldable with low-hydrogen consumables but CE ≈0.75 demands 200–300 °C preheat, controlled interpass and PWHT/re-temper to avoid HAZ cracking.
What surface finishes work on 8630-CR?
No inherent corrosion resistance — protect by phosphating, zinc/Ni plating, thermal spray or paint; nitriding and induction hardening give good wear surfaces (avoid electroplating >32 HRC without bake-out).
Can 8630-CR be formed, bent or molded?
Hot forge 1100–1200 °C and normalize afterwards; cold forming only in the annealed condition with generous bend radii.
What is the maximum service temperature of 8630-CR?
8630-CR is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 8630-HR and 8630-CD?
HR is the default condition — mill hot-rolled bar/plate as most commonly stocked; buy when parts will be heat treated after machining. CD: cold-drawn bar for good size tolerance, straightness and improved machined finish without further heat treatment. Yield strength is 415 MPa in HR versus 655 MPa in CD.
Can FabDigit make parts in 8630-CR?
Yes — 8630-CR 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 J404 — Chemical Compositions of SAE Alloy Steels — SAE International (2021)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM (2020)
- ASTM A322 — Alloy Steel Bars, Standard Grades — ASTM (2019)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- NACE MR0175 / ISO 15156 — Materials for H2S-containing environments — NACE/ISO (2015)
- Machinery's Handbook, 31st ed. — Industrial Press (2020)
- Mysteel / SMM (2025)
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.