Steel 5150-CR (Cold rolled)
Supply condition
AISI/SAE 5150 · UNS G51500
Cold-rolled strip/sheet for stamped spring and clip parts, usually finished by hardening and tempering.
Values for the CR condition
Other 5150 tempers and conditions
5150 is listed in 11 conditions; see the grade overview at 5150.
Compare all 11 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Temper | Softest condition (spheroidize/full anneal) for heavy machining or cold forming before hardening. | 360 | 675 | 22 | 197 HB | — |
HRDefault Hot rolled | As-rolled bar/plate stock for parts that will be machined and then heat treated. | 460 | 800 | 18 | 20 HRC | 8 % IACS |
Heat Treat State | Air cooled from ~870 °C for uniform fine grain and improved machined-part consistency before final hardening. | 530 | 870 | 20.7 | 25 HRC | 8 % IACS |
CRThis page Cold rolled | Cold-rolled strip/sheet for stamped spring and clip parts, usually finished by hardening and tempering. | 700 | 880 | 10 | 25 HRC | 8 % IACS |
Cold drawn | Cold-drawn bar giving tight size tolerance, better surface finish and higher as-supplied strength than hot rolled. | 760 | 900 | 12 | 27 HRC | 8 % IACS |
Q&T, tempered 650 °C | Tough, lower-strength condition for shafts and fasteners needing impact resistance and easier machining. | 800 | 870 | 20 | 27 HRC | 8 % IACS |
Quenched and tempered | Generic oil-quenched and tempered condition (~540 °C temper) — the usual structural condition for shafts, gears and heavy springs. | 1,080 | 1,150 | 15 | 37 HRC | — |
Q&T, tempered 540 °C | General-purpose machine-part condition with good strength/toughness balance. | 1,080 | 1,150 | 15 | 36 HRC | 8 % IACS |
Q&T, tempered 425 °C | Balanced high-strength spring/gear condition, typical for leaf and coil springs. | 1,360 | 1,450 | 9 | 44 HRC | 7.5 % IACS |
Q&T, tempered 315 °C | High-hardness spring condition; avoid this range if impact toughness matters (tempered-martensite embrittlement). | 1,570 | 1,730 | 6 | 49 HRC | 7.5 % IACS |
Q&T, tempered 205 °C | Maximum-hardness condition for wear surfaces and small springs; very low ductility and notch sensitivity. | 1,730 | 1,930 | 5.5 | 52 HRC | — |
What is 5150-CR?
5150-CR is 5150 supplied in the CR condition — cold-rolled strip/sheet for stamped spring and clip parts, usually finished by hardening and tempering. 5150-CR has a yield strength of 700 MPa (102 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 81% of steel grades. Elongation at break is 10% and the elastic modulus is 205 GPa (29.7 Msi). 5150-CR 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; CR is available on request or by drawing note.
Advantages
- High strength — 700 MPa (102 ksi), better than 81% of steel grades
Limitations
- Limited ductility — 10%, worse than 91% of steel grades
- Limited service temperature — 250°C (482 °F), worse than 85% of steel grades
- Difficult to weld — 22/100, worse than 81% of steel grades
5150-CR properties
Typical room-temperature values for 5150-CR; 21 are specific to this condition. Other listed values are 5150 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
5150-CR 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).
Mechanical16
5150-CR has a yield strength of 700 MPa (102 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 81% of steel grades. Elongation at break is 10% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
5150-CR is rated for continuous service to 250°C (482 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12.4 µm/m·K (6.89 µin/in·°F).
Electrical3
5150-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 5150-CR takes about 26 MJ of energy and emits 2 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 30%.
Manufacturability7
5150-CR's machinability is fair (50/100, worse than 53% of steel grades); weldability poor (22/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 5150-CR
Is 5150 easy to machine?
Machine in the annealed or ≤32 HRC condition with carbide tooling and rigid setups; above 40 HRC use CBN/ceramic or grinding.
Can 5150 be welded?
Poor weldability (CE ≈ 0.75) — preheat 250–350 °C, low-hydrogen consumables and immediate post-weld temper are mandatory.
Can 5150 be formed, bent or molded?
Hot forge 1150–1200 °C, finish above 900 °C, then anneal or normalize; cold forming only for light bends in annealed strip.
What surface finishes work on 5150?
No natural corrosion resistance — phosphate + oil, black oxide, zinc plating, paint or hard chrome; shot peen springs to boost fatigue life.
5150 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 | 0.48 – 0.53 | 0.5 |
| Mn | 0.7 – 0.9 | 0.8 |
| Si | 0.15 – 0.35 | 0.25 |
| Cr | 0.7 – 0.9 | 0.8 |
| P | ≤ 0.04 | — |
| S | ≤ 0.04 | — |
| Fe | balance | — |
5150-CR — frequently asked
What is 5150-CR used for?
5150-CR is typically used for coil springs, leaf springs, axle and drive shafts, gears and gear blanks, structural forgings and torsion bars. In short: workhorse chrome spring bar.
What is the yield strength of 5150-CR?
5150-CR has a typical yield strength of 700 MPa (102 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 81% of steel grades. Strength varies by condition: see the 11 listed tempers.
Is 5150-CR easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machine in the annealed or ≤32 HRC condition with carbide tooling and rigid setups; above 40 HRC use CBN/ceramic or grinding.
Can 5150-CR be welded?
Not readily — weldability is rated poor (22/100). Poor weldability (CE ≈ 0.75) — preheat 250–350 °C, low-hydrogen consumables and immediate post-weld temper are mandatory.
What surface finishes work on 5150-CR?
No natural corrosion resistance — phosphate + oil, black oxide, zinc plating, paint or hard chrome; shot peen springs to boost fatigue life.
Can 5150-CR be formed, bent or molded?
Hot forge 1150–1200 °C, finish above 900 °C, then anneal or normalize; cold forming only for light bends in annealed strip.
What is the maximum service temperature of 5150-CR?
5150-CR 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 5150-HR and 5150-CD?
HR is the default condition — as-rolled bar/plate stock for parts that will be machined and then heat treated. CD: cold-drawn bar giving tight size tolerance, better surface finish and higher as-supplied strength than hot rolled. Yield strength is 460 MPa in HR versus 760 MPa in CD.
Can FabDigit make parts in 5150-CR?
Yes — 5150-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)
- GB/T 3077 (50Cr) — SAC (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- 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.