Steel ZG35CrMo Q&T (Quenched and tempered)
Heat-treated state · default condition
Default stocked/ordered condition: best strength-toughness balance for gear blanks, sprockets, rims and highly loaded machine castings.
Values for the Q&T condition
Other ZG35CrMo tempers and conditions
ZG35CrMo is listed in 7 conditions; see the grade overview at ZG35CrMo.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Choose for maximum machinability and dimensional stability before final hardening, or for weld-repair of heavy castings. | 350 | 600 | 17 | 185 HB | — |
As fabricated | Rough non-critical castings only; segregated as-cast structure with low toughness, essentially always heat treated instead. | 390 | 660 | 8 | 17 HRC | 7.8 % IACS |
Normalized and tempered | Standard economical condition for large or thick-section castings where through-quenching is impractical; meets the JB/T 6402 normalized+tempered property class. | 430 | 640 | 15 | 205 HB | — |
Stress relieved | Specify after weld repair or heavy rough machining of N+T / Q&T castings to relieve residual stress with minimal property change. | 540 | 730 | 15 | 20 HRC | 7.8 % IACS |
Q&TDefaultThis page Quenched and tempered | Default stocked/ordered condition: best strength-toughness balance for gear blanks, sprockets, rims and highly loaded machine castings. | 570 | 760 | 14 | 23 HRC | — |
Induction hardened | Use for gear teeth and journal surfaces needing a hard wear layer over a tough Q&T core. | 570 | 760 | 11 | 52 HRC | 7.6 % IACS |
Quenched and low-temperature tempered | Pick when higher wear resistance and yield strength are needed (gear rims, crusher parts) and reduced ductility is acceptable. | 760 | 930 | 11 | 31 HRC | — |
What is ZG35CrMo Q&T?
ZG35CrMo Q&T is ZG35CrMo heat treated to Q&T — default stocked/ordered condition: best strength-toughness balance for gear blanks, sprockets, rims and highly loaded machine castings. ZG35CrMo Q&T has a yield strength of 570 MPa (82.7 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 74% of steel grades. Elongation at break is 14% and the elastic modulus is 208 GPa (30.2 Msi). ZG35CrMo Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Advantages
- High service temperature — 450°C (842 °F), better than 86% of steel grades
Limitations
- Limited formability — 10/100, worse than 95% of steel grades
- Limited ductility — 14%, worse than 75% of steel grades
ZG35CrMo Q&T properties
Typical room-temperature values for ZG35CrMo Q&T; 13 are specific to this condition. Other listed values are ZG35CrMo reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
ZG35CrMo Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
ZG35CrMo Q&T has a yield strength of 570 MPa (82.7 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 74% of steel grades. Elongation at break is 14% and the elastic modulus is 208 GPa (30.2 Msi).
Thermal6
ZG35CrMo Q&T is rated for continuous service to 450°C (842 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 56% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical2
ZG35CrMo Q&T has an electrical resistivity of 2.2×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is not recommended (13/100), better than 66% of steel grades.
Sustainability4
Producing a kilogram of ZG35CrMo Q&T takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 75%.
Manufacturability7
ZG35CrMo Q&T's machinability is fair (45/100, worse than 65% of steel grades); weldability fair (40/100); formability not recommended (10/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ZG35CrMo Q&T
Is ZG35CrMo easy to machine?
Machine in the annealed or N+T condition where possible; at 217–269 HB use rigid setups, carbide tooling and moderate speeds, and allow for hard scale/skin on unblasted castings.
Can ZG35CrMo be welded?
Weld with low-hydrogen Cr-Mo consumables (e.g. E8018-B2), preheat 250–350 °C, maintain interpass temperature, and post-weld temper below the original tempering temperature.
Can ZG35CrMo be formed, bent or molded?
Sand-cast with generous risering and 2–2.5 % shrinkage allowance; avoid hot tears at section changes and always heat treat to break up the as-cast structure.
What surface finishes work on ZG35CrMo?
Shot-blast then paint, phosphate or zinc/hard-chrome plate for corrosion protection; nitriding or induction hardening can be applied to wear surfaces.
ZG35CrMo 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 |
|---|---|---|
| CJB/T 6402 ZG35CrMo | 0.3 – 0.37 | 0.34 |
| Si | 0.3 – 0.6 | 0.45 |
| Mn | 0.5 – 0.8 | 0.65 |
| Cr | 0.8 – 1.2 | 1 |
| Mo | 0.2 – 0.3 | 0.25 |
| Niresidual limit | ≤ 0.3 | — |
| Curesidual limit | ≤ 0.3 | — |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.04 | 0.02 |
| Fe | balance | — |
ZG35CrMo Q&T — frequently asked
What is ZG35CrMo Q&T used for?
ZG35CrMo Q&T is typically used for gear housings, heavy machinery structural parts and shaft supports. In short: tough general-purpose Cr-Mo casting; cast equivalent of 35CrMo; more weldable than ZG42CrMo.
What is the yield strength of ZG35CrMo Q&T?
ZG35CrMo Q&T has a typical yield strength of 570 MPa (82.7 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 74% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is ZG35CrMo Q&T easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machine in the annealed or N+T condition where possible; at 217–269 HB use rigid setups, carbide tooling and moderate speeds, and allow for hard scale/skin on unblasted castings.
Can ZG35CrMo Q&T be welded?
With care — weldability is rated fair (40/100). Weld with low-hydrogen Cr-Mo consumables (e.g. E8018-B2), preheat 250–350 °C, maintain interpass temperature, and post-weld temper below the original tempering temperature.
What surface finishes work on ZG35CrMo Q&T?
Shot-blast then paint, phosphate or zinc/hard-chrome plate for corrosion protection; nitriding or induction hardening can be applied to wear surfaces.
Can ZG35CrMo Q&T be formed, bent or molded?
Sand-cast with generous risering and 2–2.5 % shrinkage allowance; avoid hot tears at section changes and always heat treat to break up the as-cast structure.
What is the maximum service temperature of ZG35CrMo Q&T?
ZG35CrMo Q&T is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ZG35CrMo Q&T and ZG35CrMo-A?
Q&T is the default condition — default stocked/ordered condition: best strength-toughness balance for gear blanks, sprockets, rims and highly loaded machine castings. A: choose for maximum machinability and dimensional stability before final hardening, or for weld-repair of heavy castings. Yield strength is 570 MPa in Q&T versus 350 MPa in A.
Sources
- ASTM A217/A217M (Grade WC6) — ASTM International (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Steel Castings Handbook — Steel Founders' Society of America / ASM (1995)
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.