Steel 5CrMnMo QT 34-37 HRC
Hardness band
GB 5CrMnMo
Maximum toughness / crack resistance for large forging die blocks working under heavy impact.
Values for the QT 34-37 HRC condition
Other 5CrMnMo tempers and conditions
5CrMnMo is listed in 9 conditions; see the grade overview at 5CrMnMo.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault spheroidize/soft annealed bar as delivered | Standard stocking condition for forged/rolled bar and blocks: soft enough for die sinking before hardening. | 500 | 780 | 18 | 18 HRC | 7.2 % IACS |
Normalized | Grain refinement / structure homogenization step after forging, before spheroidize annealing; too hard for extensive machining. | 600 | 950 | 12 | 29 HRC | 7.2 % IACS |
dovetail / shank zone temper | Soft-back condition specified for die dovetails and shanks to avoid brittle fracture at clamping features. | 870 | 1,000 | 16 | 33 HRC | 7.2 % IACS |
QT 34-37 HRCThis page temper ~580–600 °C (large dies > 375 mm) | Maximum toughness / crack resistance for large forging die blocks working under heavy impact. | 960 | 1,100 | 14 | 36 HRC | — |
temper ~550–570 °C (dies 325–375 mm) | Toughness-biased setting for larger hammer dies and deep-impression cavities. | 1,100 | 1,250 | 12 | 39 HRC | — |
Q&T + gas/ion nitrided surface | Post-treatment for die cavities needing extra wear and washout resistance; nitride at ≤ tempering temperature to avoid softening the core. | 1,100 | 1,250 | 11 | 40 HRC | 6.9 % IACS |
temper ~520–540 °C (dies 275–325 mm) | Balanced wear/toughness setting for medium hammer dies and hot trimming tools. | 1,230 | 1,400 | 10 | 42 HRC | — |
oil quench + temper ~490–510 °C (small dies, height < 275 mm) | Highest working hardness: small hammer dies, inserts and punches where wear resistance dominates. | 1,350 | 1,550 | 9 | 45 HRC | — |
As-quenched | Intermediate condition only — must be tempered immediately; brittle and highly stressed. | 1,500 | 1,950 | 1 | 55 HRC | 6.6 % IACS |
What is 5CrMnMo QT 34-37 HRC?
5CrMnMo QT 34-37 HRC is 5CrMnMo heat treated to QT 34-37 HRC — maximum toughness / crack resistance for large forging die blocks working under heavy impact. 5CrMnMo QT 34-37 HRC has a yield strength of 960 MPa (139 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 91% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi). 5CrMnMo QT 34-37 HRC has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 87% of steel grades. It melts at 1,420°C (2,588 °F). Annealed is the default condition FabDigit quotes; QT 34-37 HRC is available on request or by drawing note.
Advantages
- High service temperature — 520°C (968 °F), better than 92% of steel grades
- High strength — 960 MPa (139 ksi), better than 91% of steel grades
Limitations
- Difficult to machine — 30/100, worse than 89% of steel grades
- High embodied carbon — 2.6 kg CO₂/kg, worse than 87% of steel grades
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades
- Limited ductility — 14%, worse than 75% of steel grades
5CrMnMo QT 34-37 HRC properties
Typical room-temperature values for 5CrMnMo QT 34-37 HRC; 12 are specific to this condition. Other listed values are 5CrMnMo reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
5CrMnMo QT 34-37 HRC has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 87% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical17
5CrMnMo QT 34-37 HRC has a yield strength of 960 MPa (139 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 91% of steel grades. Elongation at break is 14% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
5CrMnMo QT 34-37 HRC is rated for continuous service to 520°C (968 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
5CrMnMo QT 34-37 HRC conducts electricity at 7.2 % IACS, worse than 71% of steel grades.
Chemical & Environmental2
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 5CrMnMo QT 34-37 HRC takes about 34 MJ of energy and emits 2.6 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 45%.
Manufacturability8
5CrMnMo QT 34-37 HRC's machinability is poor (30/100, worse than 89% of steel grades); weldability fair (35/100); formability poor (30/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 5CrMnMo QT 34-37 HRC
Is 5CrMnMo easy to machine?
Cut in the spheroidize-annealed state (≤241 HB) with coated carbide at moderate speed; after tempering above 38 HRC use rigid setups, ceramic/CBN or EDM for cavity finishing and stress-relieve before final hardening.
Can 5CrMnMo be welded?
Repair welding only — preheat 300–400 °C, use matching or 5CrNiMo-type filler, keep interpass temperature and temper immediately at 20–30 °C below the last tempering temperature to avoid HAZ cracking.
Can 5CrMnMo be formed, bent or molded?
Hot forge 1100–1150 °C, finish above 850 °C, cool slowly in furnace or ash, then normalize 850–870 °C and spheroidize anneal 760–780 °C; no cold forming.
What surface finishes work on 5CrMnMo?
Cavities are polished or textured then usually nitrided/oxide-blackened; no anodizing — protect with oil, phosphate or vapour-phase inhibitor since the steel rusts freely.
5CrMnMo 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 | 0.5 – 0.6 | 0.55 |
| Si | 0.25 – 0.6 | 0.4 |
| MnMn replaces Ni of 5CrNiMo for hardenability | 1.2 – 1.6 | 1.4 |
| Cr | 0.6 – 0.9 | 0.75 |
| Motemper-brittleness suppression | 0.15 – 0.3 | 0.22 |
| Niresidual | ≤ 0.25 | — |
| Curesidual | ≤ 0.25 | — |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
5CrMnMo QT 34-37 HRC — frequently asked
What is 5CrMnMo QT 34-37 HRC used for?
5CrMnMo QT 34-37 HRC is typically used for forging dies, hot stamping dies, die inserts and holders, hot upsetting and trimming dies, hot shear blades and mandrels for hot forming. In short: tough small-die hot-work steel; economical forging die grade; lower hardenability than 5CrNiMo.
What is the yield strength of 5CrMnMo QT 34-37 HRC?
5CrMnMo QT 34-37 HRC has a typical yield strength of 960 MPa (139 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 91% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 5CrMnMo QT 34-37 HRC easy to machine?
Not especially — machinability is rated poor (30/100, worse than 89% of steel grades). Cut in the spheroidize-annealed state (≤241 HB) with coated carbide at moderate speed; after tempering above 38 HRC use rigid setups, ceramic/CBN or EDM for cavity finishing and stress-relieve before final hardening.
Can 5CrMnMo QT 34-37 HRC be welded?
With care — weldability is rated fair (35/100). Repair welding only — preheat 300–400 °C, use matching or 5CrNiMo-type filler, keep interpass temperature and temper immediately at 20–30 °C below the last tempering temperature to avoid HAZ cracking.
What surface finishes work on 5CrMnMo QT 34-37 HRC?
Cavities are polished or textured then usually nitrided/oxide-blackened; no anodizing — protect with oil, phosphate or vapour-phase inhibitor since the steel rusts freely.
Can 5CrMnMo QT 34-37 HRC be formed, bent or molded?
Hot forge 1100–1150 °C, finish above 850 °C, cool slowly in furnace or ash, then normalize 850–870 °C and spheroidize anneal 760–780 °C; no cold forming.
What is the maximum service temperature of 5CrMnMo QT 34-37 HRC?
5CrMnMo QT 34-37 HRC is rated for continuous use to about 520°C (968 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 5CrMnMo Annealed and 5CrMnMo-Q?
Annealed is the default condition — standard stocking condition for forged/rolled bar and blocks: soft enough for die sinking before hardening. Q: intermediate condition only — must be tempered immediately; brittle and highly stressed. Yield strength is 500 MPa in Annealed versus 1,500 MPa in Q.
Sources
- GB/T 1299 (Alloy tool steels) (2014)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- Tool Steels, 5th ed. (L6 / 6F2 hot-work die steel data) — ASM International (1998)
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.