Steel A607 Grade 70 HR-CL1
Finish state · default condition
ASTM A607 Grade 70
HR-CL1 = hot-Rolled, Class 1
Standard stocked condition: maximum strength per unit weight for chassis, frames and heavy brackets where forming is moderate.
Values for the HR-CL1 condition
Other A607 Grade 70 tempers and conditions
A607 Grade 70 is listed in 5 conditions; see the grade overview at A607 Grade 70.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hot-Rolled, Class 2 | Pick when weldability and bend performance matter more than peak tensile: same 485 MPa yield but a lower minimum tensile (550 MPa) and leaner carbon. | 510 | 585 | 18 | 175 HB | 9 % IACS |
HR-CL1DefaultThis page Hot-Rolled, Class 1 | Standard stocked condition: maximum strength per unit weight for chassis, frames and heavy brackets where forming is moderate. | 515 | 620 | 16 | 185 HB | — |
Cold-Rolled, Class 2 | Thin-gauge cold-rolled option when resistance-spot-welded assemblies and bending demand the leaner Class 2 chemistry. | 515 | 595 | 15 | 180 HB | 9 % IACS |
Hot-Rolled Pickled & Oiled, Class 1 | Scale-free hot-rolled coil for laser cutting, roll forming and direct painting without shot blasting. | 515 | 620 | 16 | 185 HB | 9 % IACS |
Cold-Rolled, Class 1 | Use for thin gauge, tight thickness tolerance and a smooth paintable surface; ductility is lower than hot-rolled. | 525 | 630 | 13 | 195 HB | 9 % IACS |
What is A607 Grade 70 HR-CL1?
A607 Grade 70 HR-CL1 is A607 Grade 70 supplied in the HR-CL1 condition — standard stocked condition: maximum strength per unit weight for chassis, frames and heavy brackets where forming is moderate. A607 Grade 70 HR-CL1 has a yield strength of 515 MPa (74.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 66% of steel grades. Elongation at break is 16% and the elastic modulus is 205 GPa (29.7 Msi). A607 Grade 70 HR-CL1 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F).
Advantages
- Readily welded — 72/100, better than 75% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
A607 Grade 70 HR-CL1 properties
Typical room-temperature values for A607 Grade 70 HR-CL1; 10 are specific to this condition. Other listed values are A607 Grade 70 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
A607 Grade 70 HR-CL1 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F).
Mechanical14
A607 Grade 70 HR-CL1 has a yield strength of 515 MPa (74.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 66% of steel grades. Elongation at break is 16% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
A607 Grade 70 HR-CL1 is rated for continuous service to 350°C (662 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
A607 Grade 70 HR-CL1 conducts electricity at 9 % IACS, better than 71% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of A607 Grade 70 HR-CL1 takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
A607 Grade 70 HR-CL1's machinability is fair (48/100, worse than 57% of steel grades); weldability very good (72/100); formability fair (48/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with A607 Grade 70 HR-CL1
Is A607 Grade 70 easy to machine?
Machines like a 500 MPa-class carbon steel — use rigid setups, coated carbide and positive rake; punching requires ~1.4× the force of mild steel and larger die clearance.
Can A607 Grade 70 be welded?
Low carbon equivalent gives good GMAW/GTAW/RSW weldability with ER70S-6 (Class 2 preferred for heavy weldments); avoid excessive heat input, which dissolves Nb/V precipitates and softens the HAZ.
Can A607 Grade 70 be formed, bent or molded?
Cold-formable but with high springback and limited stretch — use generous bend radii (≥2–3 t transverse to rolling), bend across the rolling direction, and allow for a 3–8° overbend.
What surface finishes work on A607 Grade 70?
No inherent corrosion resistance: specify pickling or blasting, then phosphate + e-coat, powder coat, zinc plating or hot-dip galvanizing; anodizing is not applicable.
A607 Grade 70 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 |
|---|---|---|
| Cheat analysis maximum; Class 2 heats are usually leaner | ≤ 0.26 | 0.1 |
| Mnmaximum for Grades 65 and 70 | ≤ 1.65 | 1.3 |
| P | ≤ 0.04 | 0.02 |
| Ssulfide shape control common for improved formability | ≤ 0.04 | 0.01 |
| Siproducer practice; not always a specification limit | ≤ 0.9 | 0.2 |
| Nbcolumbium; Nb and/or V must total the micro-alloy addition | 0.01 – 0.05 | 0.03 |
| Valternative or supplement to Nb | 0.01 – 0.15 | 0.06 |
| Nused with V for precipitation strengthening | ≤ 0.02 | 0.01 |
| Fe | balance | — |
A607 Grade 70 HR-CL1 — frequently asked
What is A607 Grade 70 HR-CL1 used for?
A607 Grade 70 HR-CL1 is typically used for truck frame components, wheel rims and structural stampings. In short: 70 ksi HSLA sheet; thinner gauge, same load; less formable than Grade 50.
What is the yield strength of A607 Grade 70 HR-CL1?
A607 Grade 70 HR-CL1 has a typical yield strength of 515 MPa (74.7 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 66% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is A607 Grade 70 HR-CL1 easy to machine?
Reasonably — machinability is rated fair (48/100, worse than 57% of steel grades). Machines like a 500 MPa-class carbon steel — use rigid setups, coated carbide and positive rake; punching requires ~1.4× the force of mild steel and larger die clearance.
Can A607 Grade 70 HR-CL1 be welded?
Yes — weldability is rated very good (72/100). Low carbon equivalent gives good GMAW/GTAW/RSW weldability with ER70S-6 (Class 2 preferred for heavy weldments); avoid excessive heat input, which dissolves Nb/V precipitates and softens the HAZ.
What surface finishes work on A607 Grade 70 HR-CL1?
No inherent corrosion resistance: specify pickling or blasting, then phosphate + e-coat, powder coat, zinc plating or hot-dip galvanizing; anodizing is not applicable.
Can A607 Grade 70 HR-CL1 be formed, bent or molded?
Cold-formable but with high springback and limited stretch — use generous bend radii (≥2–3 t transverse to rolling), bend across the rolling direction, and allow for a 3–8° overbend.
What is the maximum service temperature of A607 Grade 70 HR-CL1?
A607 Grade 70 HR-CL1 is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A607 Grade 70 HR-CL1 and A607 Grade 70 CR-CL1?
HR-CL1 is the default condition — standard stocked condition: maximum strength per unit weight for chassis, frames and heavy brackets where forming is moderate. CR-CL1: use for thin gauge, tight thickness tolerance and a smooth paintable surface; ductility is lower than hot-rolled. Yield strength is 515 MPa in HR-CL1 versus 525 MPa in CR-CL1.
Sources
- ASTM A607 — Steel, Sheet and Strip, HSLA, Columbium or Vanadium, or Both, Hot-Rolled and Cold-Rolled (withdrawn, replaced by A1011/A1018) — ASTM International (2004)
- ASTM A1011/A1011M — HSLAS and HSLAS-F Hot-Rolled Sheet and Strip — ASTM International (2018)
- ASTM A1008/A1018 — Cold-Rolled HSLAS Sheet — ASTM International (2020)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (HSLA sheet steels) — ASM International (1990)
- ASTM A370 — Mechanical Testing of Steel Products (hardness conversions) — ASTM International (2022)
- worldsteel Life Cycle Inventory — hot-rolled coil — World Steel Association (2021)
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.