Steel 1345-HR (Hot rolled)
Supply condition
AISI/SAE 1345 · UNS G13450
Cheapest mill condition for parts that will be forged, normalized or heat treated after rough machining.
Values for the HR condition
Other 1345 tempers and conditions
1345 is listed in 8 conditions; see the grade overview at 1345.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ADefault Solution annealed | Pick for maximum machinability and stock removal before final quench-and-temper or for lightly loaded parts. | 440 | 725 | 20 | 205 HB | — |
HRThis page Hot rolled | Cheapest mill condition for parts that will be forged, normalized or heat treated after rough machining. | 470 | 780 | 17 | 225 HB | — |
Normalized | Use to homogenize forgings and get uniform mid-strength properties without quench distortion. | 580 | 890 | 18 | 26 HRC | — |
Stress relieved | Use on cold-drawn bar or rough-machined parts to cut distortion in later machining while keeping most cold-work strength. | 620 | 790 | 15 | 21 HRC | 8 % IACS |
Cold drawn | Choose for close-tolerance bar with raised yield strength and good surface, where no further heat treatment is planned. | 690 | 830 | 12 | 23 HRC | — |
Q&T 28–32 HRC | General-purpose tough condition for shafts and levers needing good impact strength with moderate hardness. | 840 | 985 | 17 | 30 HRC | — |
Q&T 33–38 HRC | Higher-strength option for gears, spindles and highly loaded bolting where some ductility is still required. | 1,030 | 1,160 | 14 | 36 HRC | — |
Q&T 40–45 HRC | Maximum strength/wear condition for small cross-sections; accept low toughness and notch sensitivity. | 1,260 | 1,400 | 11 | 43 HRC | — |
What is 1345-HR?
1345-HR is 1345 supplied in the HR condition — cheapest mill condition for parts that will be forged, normalized or heat treated after rough machining. 1345-HR has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 57% of steel grades. Elongation at break is 17% and the elastic modulus is 205 GPa (29.7 Msi). 1345-HR 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). A is the default condition FabDigit quotes; HR is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
Limitations
- Low fracture toughness — 60 MPa·√m (54.6 ksi·√in), worse than 78% of steel grades
1345-HR properties
Typical room-temperature values for 1345-HR; 11 are specific to this condition. Other listed values are 1345 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
1345-HR 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
1345-HR has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 57% of steel grades. Elongation at break is 17% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1345-HR is rated for continuous service to 400°C (752 °F). It conducts heat at 43 W/m·K (24.8 BTU/hr·ft·°F), better than 51% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
1345-HR conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 1345-HR takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
1345-HR's machinability is fair (42/100, worse than 73% of steel grades); weldability poor (30/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1345-HR
Is 1345 easy to machine?
Machine in the annealed or cold-drawn state with rigid setups and carbide tooling; the high Mn work-hardens and gives gummy chips, so use positive rake, generous feeds and flood coolant, and finish-grind after hardening above ~35 HRC.
Can 1345 be welded?
Poor weldability (carbon equivalent >0.8): preheat 250–350 °C, use low-hydrogen consumables or matching filler, control interpass temperature and temper/stress-relieve immediately after welding to avoid martensitic cracking.
Can 1345 be formed, bent or molded?
Hot forge at 1100–1200 °C and normalize afterwards; cold forming is limited to gentle bends in the annealed condition — the high-Mn medium-carbon matrix cracks in tight radii and cold-drawn bar has little remaining ductility.
What surface finishes work on 1345?
No corrosion resistance — protect with oil, black oxide, manganese phosphate, zinc or Ni plating (bake to relieve hydrogen above 32 HRC), or paint; polishes well after hardening and takes induction-hardened, ground bearing surfaces.
1345 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/AISI 1345 heat analysis | 0.43 – 0.48 | 0.46 |
| Mn13xx manganese series | 1.6 – 1.9 | 1.75 |
| Sifor killed steel; not applicable to some semi-killed grades | 0.15 – 0.35 | 0.25 |
| P | ≤ 0.04 | — |
| S | ≤ 0.04 | — |
| Fe | balance | — |
1345-HR — frequently asked
What is 1345-HR used for?
1345-HR is typically used for shafts, axles, machine parts and forgings. In short: deeper hardening than 1335; poor weldability, high CE; forging and shaft grade.
What is the yield strength of 1345-HR?
1345-HR has a typical yield strength of 470 MPa (68.2 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 57% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 1345-HR easy to machine?
Not especially — machinability is rated fair (42/100, worse than 73% of steel grades). Machine in the annealed or cold-drawn state with rigid setups and carbide tooling; the high Mn work-hardens and gives gummy chips, so use positive rake, generous feeds and flood coolant, and finish-grind after hardening above ~35 HRC.
Can 1345-HR be welded?
Not readily — weldability is rated poor (30/100). Poor weldability (carbon equivalent >0.8): preheat 250–350 °C, use low-hydrogen consumables or matching filler, control interpass temperature and temper/stress-relieve immediately after welding to avoid martensitic cracking.
What surface finishes work on 1345-HR?
No corrosion resistance — protect with oil, black oxide, manganese phosphate, zinc or Ni plating (bake to relieve hydrogen above 32 HRC), or paint; polishes well after hardening and takes induction-hardened, ground bearing surfaces.
Can 1345-HR be formed, bent or molded?
Hot forge at 1100–1200 °C and normalize afterwards; cold forming is limited to gentle bends in the annealed condition — the high-Mn medium-carbon matrix cracks in tight radii and cold-drawn bar has little remaining ductility.
What is the maximum service temperature of 1345-HR?
1345-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 1345-A and 1345 QT40-45?
A is the default condition — pick for maximum machinability and stock removal before final quench-and-temper or for lightly loaded parts. QT40-45: maximum strength/wear condition for small cross-sections; accept low toughness and notch sensitivity. Yield strength is 440 MPa in A versus 1,260 MPa in QT40-45.
Sources
- SAE J403 — Chemical Compositions of SAE Carbon and Alloy Steels (13xx) — SAE International (2014)
- SAE J404 — Chemical Compositions of SAE Alloy Steels — SAE International (2021)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought, General Requirements — ASTM (2020)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol. 4A — Steel Heat Treating Fundamentals and Processes — ASM International (2013)
- Machinery's Handbook, 31st ed. (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.