Steel Y45MnV · hardness band
Steel Y45MnV QT-32-38HRC
Properties of the QT-32-38HRC condition, compared with the other Y45MnV tempers.
Higher-strength shaft condition where load capacity outweighs machining cost and impact demands are moderate.
What is Y45MnV QT-32-38HRC?
Y45MnV QT-32-38HRC is Y45MnV heat treated to QT-32-38HRC — higher-strength shaft condition where load capacity outweighs machining cost and impact demands are moderate. Y45MnV QT-32-38HRC has a yield strength of 930 MPa (135 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 90% of steel grades. Elongation at break is 12% and the elastic modulus is 210 GPa (30.5 Msi). Y45MnV QT-32-38HRC 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; QT-32-38HRC is available on request or by drawing note.
Advantages
- High strength — 930 MPa (135 ksi), better than 90% of steel grades
Limitations
- Hard to polish — 40/100, worse than 96% of steel grades
- Limited ductility — 12%, worse than 84% of steel grades
- Low fracture toughness — 55 MPa·√m (50.1 ksi·√in), worse than 83% of steel grades
- Difficult to weld — 22/100, worse than 81% of steel grades
Y45MnV QT-32-38HRC properties
Typical room-temperature values for Y45MnV QT-32-38HRC — 10 properties are specific to this condition; the rest are grade-level values shared by every Y45MnV temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
Y45MnV QT-32-38HRC 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
Y45MnV QT-32-38HRC has a yield strength of 930 MPa (135 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 90% of steel grades. Elongation at break is 12% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
Y45MnV QT-32-38HRC is rated for continuous service to 400°C (752 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
Y45MnV QT-32-38HRC conducts electricity at 8.6 % IACS, better than 66% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 87% of steel grades.
Sustainability4
Producing a kilogram of Y45MnV QT-32-38HRC takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
Y45MnV QT-32-38HRC's machinability is fair (44/100, worse than 71% of steel grades); weldability poor (22/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other Y45MnV tempers and conditions
Y45MnV is also supplied in 6 other conditions. The full side-by-side table is on the Y45MnV overview.
- HRDefaultStandard stock condition: strength comes from V microalloying during air cooling, so parts can be machined straight from bar.560 MPa yield · 25 HRC
- QT-32-38HRCHigher-strength shaft condition where load capacity outweighs machining cost and impact demands are moderate.930 MPa yield · 35 HRC
- CDChoose for close-tolerance bright bar feeding automatic lathes where straightness and surface finish matter.780 MPa yield · 30 HRC
- QT-25-30HRCGeneral-purpose tempered condition when better toughness and property uniformity than the as-rolled bar is required.720 MPa yield · 28 HRC
- NUsed to homogenise forged blanks and give a uniform ferrite–pearlite structure before finish machining.510 MPa yield · 21 HRC
- APick when maximum machinability or cold-working ability is needed before a later hardening operation.390 MPa yield · 190 HB
Working with Y45MnV QT-32-38HRC
Is Y45MnV easy to machine?
Turns and drills well on automatics thanks to MnS chip breakers; use rigid setups, coated carbide at 120–200 m/min and avoid dwelling, since work-hardened skin on cold-drawn bar dulls edges.
Can Y45MnV be welded?
Not recommended for structural welds — high carbon plus 0.04–0.08 % S gives hot cracking and hard HAZ; if unavoidable preheat 250–300 °C, use low-hydrogen consumables and post-weld temper.
Can Y45MnV be formed, bent or molded?
Hot forge at 1150–850 °C followed by controlled air cooling to develop the non-quenched strength; cold bending or heading is poor because sulfide stringers open transverse cracks.
What surface finishes work on Y45MnV?
Requires protective coating — phosphate + oil, zinc or Mn phosphate, black oxide, or hard chrome on journals; polishing is limited by sulfide pull-out so avoid decorative mirror finishes.
Y45MnV 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 | 0.42 – 0.5 | 0.46 |
| Sisome mill practices run 0.30–0.60 for solid-solution strengthening | 0.17 – 0.37 | 0.27 |
| Mncombines with S to form machinable MnS | 1 – 1.4 | 1.2 |
| VV(C,N) precipitation strengthening on air cooling | 0.06 – 0.13 | 0.1 |
| Sintentional, free-cutting addition | 0.04 – 0.08 | 0.06 |
| P | ≤ 0.06 | 0.03 |
| Crresidual | ≤ 0.3 | — |
| Niresidual | ≤ 0.3 | — |
| Curesidual | ≤ 0.25 | — |
| Fe | balance | — |
Y45MnV QT-32-38HRC — frequently asked
What is Y45MnV QT-32-38HRC used for?
Y45MnV QT-32-38HRC is typically used for crankshafts, high-load shafts and automotive components. In short: strongest grade in family; microalloyed, no quench needed; 860 MPa with 14 % elongation.
What is the yield strength of Y45MnV QT-32-38HRC?
Y45MnV QT-32-38HRC has a typical yield strength of 930 MPa (135 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 90% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is Y45MnV QT-32-38HRC easy to machine?
Not especially — machinability is rated fair (44/100, worse than 71% of steel grades). Turns and drills well on automatics thanks to MnS chip breakers; use rigid setups, coated carbide at 120–200 m/min and avoid dwelling, since work-hardened skin on cold-drawn bar dulls edges.
Can Y45MnV QT-32-38HRC be welded?
Not readily — weldability is rated poor (22/100). Not recommended for structural welds — high carbon plus 0.04–0.08 % S gives hot cracking and hard HAZ; if unavoidable preheat 250–300 °C, use low-hydrogen consumables and post-weld temper.
What surface finishes work on Y45MnV QT-32-38HRC?
Requires protective coating — phosphate + oil, zinc or Mn phosphate, black oxide, or hard chrome on journals; polishing is limited by sulfide pull-out so avoid decorative mirror finishes.
Can Y45MnV QT-32-38HRC be formed, bent or molded?
Hot forge at 1150–850 °C followed by controlled air cooling to develop the non-quenched strength; cold bending or heading is poor because sulfide stringers open transverse cracks.
What is the maximum service temperature of Y45MnV QT-32-38HRC?
Y45MnV QT-32-38HRC 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 Y45MnV-HR and Y45MnV-CD?
HR is the default condition — standard stock condition: strength comes from V microalloying during air cooling, so parts can be machined straight from bar. CD: choose for close-tolerance bright bar feeding automatic lathes where straightness and surface finish matter. Yield strength is 560 MPa in HR versus 780 MPa in CD.
Sources
- GB/T 8731 (Free-cutting structural steels) (2008)
- GB/T 15712 (Non-quenched and tempered structural steels) — SAC (2016)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.16: Machining (free-machining steel ratings) — ASM International (1989)
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.