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Steel 5CrMnMo QT 30-35 HRC

Hardness band

GB 5CrMnMo

Soft-back condition specified for die dovetails and shanks to avoid brittle fracture at clamping features.

Budget cost $

Values for the QT 30-35 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 datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
AnnealedDefault
spheroidize/soft annealed bar as delivered
Standard stocking condition for forged/rolled bar and blocks: soft enough for die sinking before hardening.5007801818 HRC7.2 % IACS
Normalized
Grain refinement / structure homogenization step after forging, before spheroidize annealing; too hard for extensive machining.6009501229 HRC7.2 % IACS
QT 30-35 HRCThis page
dovetail / shank zone temper
Soft-back condition specified for die dovetails and shanks to avoid brittle fracture at clamping features.8701,0001633 HRC7.2 % IACS
temper ~580–600 °C (large dies > 375 mm)
Maximum toughness / crack resistance for large forging die blocks working under heavy impact.9601,1001436 HRC—
temper ~550–570 °C (dies 325–375 mm)
Toughness-biased setting for larger hammer dies and deep-impression cavities.1,1001,2501239 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.1,1001,2501140 HRC6.9 % IACS
temper ~520–540 °C (dies 275–325 mm)
Balanced wear/toughness setting for medium hammer dies and hot trimming tools.1,2301,4001042 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.1,3501,550945 HRC—
As-quenched
Intermediate condition only — must be tempered immediately; brittle and highly stressed.1,5001,950155 HRC6.6 % IACS

What is 5CrMnMo QT 30-35 HRC?

5CrMnMo QT 30-35 HRC is 5CrMnMo heat treated to QT 30-35 HRC — soft-back condition specified for die dovetails and shanks to avoid brittle fracture at clamping features. 5CrMnMo QT 30-35 HRC has a yield strength of 870 MPa (126 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 89% of steel grades. Elongation at break is 16% and the elastic modulus is 210 GPa (30.5 Msi). 5CrMnMo QT 30-35 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 30-35 HRC is available on request or by drawing note.

Advantages

  • High strength — 870 MPa (126 ksi), better than 89% of steel grades
  • High service temperature — 480°C (896 °F), better than 88% of steel grades

Limitations

  • Limited formability — 8/100, worse than 97% of steel grades
  • High embodied carbon — 2.6 kg CO₂/kg, worse than 87% of steel grades
  • Difficult to machine — 35/100, worse than 84% of steel grades
  • Difficult to weld — 22/100, worse than 81% of steel grades
  • Poor heat conductor — 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades

5CrMnMo QT 30-35 HRC properties

Typical room-temperature values for 5CrMnMo QT 30-35 HRC; 22 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 30-35 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).

Density7.8 g/cm³0.28 lb/in³
Melting Point (Solidus)1,420°C2,588 °F
Liquidus Temperature1,470°C2,678 °F

Mechanical17

5CrMnMo QT 30-35 HRC has a yield strength of 870 MPa (126 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 89% of steel grades. Elongation at break is 16% and the elastic modulus is 210 GPa (30.5 Msi).

Elastic (Young's) Modulus210 GPa30.5 Msi
Shear Modulus81 GPa11.7 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)1,000 MPa145 ksi
Yield Strength (0.2% offset)870 MPa126 ksi
Elongation at Break16%
Reduction in Area52%
Compressive Strength900 MPa131 ksi
Shear Strength620 MPa89.9 ksi
Fatigue Strength (Endurance Limit)470 MPa68.2 ksi
Fracture Toughness (K_IC)75 MPa·√m68.3 ksi·√in
Charpy V-Notch Impact (RT)42 J31 ft·lbf
Hardness, Brinell310 HB
Hardness, Rockwell B97 HRB
Hardness, Rockwell C33 HRC
Hardness, Vickers325 HV

Thermal6

5CrMnMo QT 30-35 HRC is rated for continuous service to 480°C (896 °F). It conducts heat at 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).

Thermal Conductivity33 W/m·K19.1 BTU/hr·ft·°F
Specific Heat Capacity460 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)12.3 µm/m·K6.8 µin/in·°F
Latent Heat of Fusion250 J/g107 BTU/lb
Max Service Temperature (continuous)480°C896 °F
Min Service Temperature-20°C-4 °F

Electrical3

5CrMnMo QT 30-35 HRC conducts electricity at 7.2 % IACS, worse than 71% of steel grades.

Electrical Conductivity7.2 % IACS
Electrical Resistivity2.4×10⁻⁷ Ω·m9.45 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental2

Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.

Corrosion ResistanceNot recommended12/100
Chemical Resistance SummaryNo practical corrosion resistance: rusts in humid air and in water-based die lubricants/coolants; must be oiled, phosphated or nitrided for storage and service.

Sustainability4

Producing a kilogram of 5CrMnMo QT 30-35 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%.

Embodied Energy (primary production)34 MJ/kg14,617 BTU/lb
Embodied Carbon (primary production)2.6 kg CO₂/kg
Embodied Water60 L/kg7.2 gal/lb
Typical Recycled Content45%

Manufacturability8

5CrMnMo QT 30-35 HRC's machinability is fair (35/100, worse than 84% of steel grades); weldability poor (22/100); formability not recommended (8/100).

MachinabilityFair35/100
Machinability Rating (AISI 1212 = 100 %)35%
WeldabilityPoor22/100
Formability (cold)Not recommended8/100
CastabilityPoor25/100
Brazeability / SolderabilityFair35/100
PolishabilityGood55/100
Anodizing Responsen/a — ferrous alloy; use nitriding, oxide blackening or phosphating instead

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with 5CrMnMo QT 30-35 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.

ElementSpec limit (wt %)Nominal
C0.5 – 0.60.55
Si0.25 – 0.60.4
MnMn replaces Ni of 5CrNiMo for hardenability1.2 – 1.61.4
Cr0.6 – 0.90.75
Motemper-brittleness suppression0.15 – 0.30.22
Niresidual≤ 0.25—
Curesidual≤ 0.25—
P≤ 0.03—
S≤ 0.03—
Febalance—

5CrMnMo QT 30-35 HRC — frequently asked

What is 5CrMnMo QT 30-35 HRC used for?

5CrMnMo QT 30-35 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 30-35 HRC?

5CrMnMo QT 30-35 HRC has a typical yield strength of 870 MPa (126 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 89% of steel grades. Strength varies by condition: see the 9 listed tempers.

Is 5CrMnMo QT 30-35 HRC easy to machine?

Not especially — machinability is rated fair (35/100, worse than 84% 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 30-35 HRC be welded?

Not readily — weldability is rated poor (22/100). 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 30-35 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 30-35 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 30-35 HRC?

5CrMnMo QT 30-35 HRC is rated for continuous use to about 480°C (896 °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

  1. GB/T 1299 (Alloy tool steels) (2014)
  2. ASM Handbook Vol.1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
  3. 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.