Steel 18KhGT
GOST 18KhGT (18ХГТ)
18KhGT (18ХГТ) is a chromium-manganese-titanium case-hardening steel of the GOST family, with titanium added for grain refinement, and is equivalent to 20CrMnTi.
Reference datasheet — 18KhGT is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the HR condition
18KhGT tempers and conditions
18KhGT is supplied in 7 conditions, soft to hard. HR is the default FabDigit quotes; the values on this page are for it.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Pick when heavy hobbing, broaching or cold forming of blanks is required before carburizing. | 400 | 640 | 23 | 170 HB | — |
HRDefault Hot rolled | Standard mill delivery condition for bar/forging stock — machine, then carburize and harden. | 500 | 760 | 18 | 197 HB | — |
Normalized | Use to homogenize forgings and refine grain before carburizing or final machining. | 560 | 820 | 16 | 18 HRC | 7.8 % IACS |
Cold drawn | Choose for small-diameter shafts and pins needing close tolerance and good surface before case hardening. | 700 | 850 | 9 | 22 HRC | 7.7 % IACS |
case 58–63 HRC, shallow case | Choose for thin-section, lightly loaded gears and small shafts where a shallow, low-distortion, wear-resistant case is enough. | 970 | 1,150 | 10 | 60 HRC | 7.5 % IACS |
Quenched (860–880 °C, oil) + tempered 200 °C | The GOST 4543 property-verification condition; also used for small through-hardened parts not needing a carburized case. | 980 | 1,150 | 11 | 38 HRC | — |
Carburized + quenched + tempered | The service condition for gears, splines and pinions: hard wear-resistant case on a tough core; grind after treatment. | 1,000 | 1,200 | 9 | 60 HRC | — |
What is 18KhGT?
18KhGT (18ХГТ) is a chromium-manganese-titanium case-hardening steel of the GOST family, with titanium added for grain refinement, and is equivalent to 20CrMnTi. It is a high-volume automotive gear steel used for gearbox and axle gearing, supplied as hot-rolled, annealed, normalized and cold-drawn bar and as forged blanks. Soft-condition values are about 500 MPa yield, 760 MPa tensile, 18 % elongation and 197 HB, with machinability 55 and a listed service limit of 350 °C. It is not corrosion resistant and cannot be welded after case hardening; 12Cr2Ni4A (9310) is the alternative where deeper hardenability and higher core strength are needed. 18KhGT 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). 18KhGT has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 63% of steel grades. Elongation at break is 18% and the elastic modulus is 210 GPa (30.5 Msi).
What is 18KhGT used for?
- Automotive transmission gears
- Gearbox shafts
- Differential ring gears and pinions
- Splined shafts
- Synchronizer hubs
- Sprockets
- Planetary gear sets
18KhGT properties
Typical room-temperature values for 18KhGT-HR; bars are the position among steel grades.
Physical3
18KhGT 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).
Mechanical13
18KhGT has a yield strength of 500 MPa (72.5 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 63% of steel grades. Elongation at break is 18% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
18KhGT is rated for continuous service to 350°C (662 °F). It conducts heat at 41 W/m·K (23.7 BTU/hr·ft·°F), worse than 62% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
18KhGT conducts electricity at 7.8 % IACS, worse than 57% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 18KhGT takes about 34 MJ of energy and emits 2.3 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 30%.
Manufacturability6
18KhGT's machinability is good (55/100, better than 62% of steel grades); weldability fair (40/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. 18KhGT is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 18KhGT
Is 18KhGT easy to machine?
Machine soft (≤217 HB, ideally isothermally annealed) with carbide at moderate speeds; after carburizing only grinding/EDM is practical, so leave 0.1–0.3 mm grind stock.
Can 18KhGT be welded?
Weldable only before case hardening — preheat 200–300 °C, low-hydrogen filler, post-weld temper; welding a carburized surface causes cracking.
Can 18KhGT be formed, bent or molded?
Excellent hot forgeability at 1150–1200 °C (stop ≥850 °C) followed by normalizing; cold forming limited, best done in the annealed state.
18KhGT 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 | 0.17 – 0.23 | 0.2 |
| Si | 0.17 – 0.37 | 0.27 |
| Mn | 0.8 – 1.1 | 0.95 |
| Cr | 1 – 1.3 | 1.15 |
| Tigrain-refining addition; GB/T 3077 20CrMnTi specifies 0.04–0.10 | 0.03 – 0.09 | 0.06 |
| Niresidual | ≤ 0.3 | — |
| Curesidual | ≤ 0.3 | — |
| S | ≤ 0.04 | — |
| P | ≤ 0.04 | — |
| Fe | balance | — |
What surface finishes work on 18KhGT?
Not corrosion resistant — protect with oil, manganese/zinc phosphate, black oxide, or Zn/Ni plating (bake to avoid hydrogen embrittlement on hardened parts); shot peening boosts gear-tooth fatigue life.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 18KhGT in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- GOST
- 18ХГТ
- Similar grades
- 20CrMnTi
How much does 18KhGT cost?
18KhGT is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
18KhGT — frequently asked
What is 18KhGT used for?
18KhGT is typically used for automotive transmission gears, gearbox shafts, differential ring gears and pinions, splined shafts, synchronizer hubs and sprockets. In short: standard automotive gear steel; titanium-refined fine grain; nickel-free carburizing grade.
What is the yield strength of 18KhGT?
18KhGT has a typical yield strength of 500 MPa (72.5 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 63% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is 18KhGT easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machine soft (≤217 HB, ideally isothermally annealed) with carbide at moderate speeds; after carburizing only grinding/EDM is practical, so leave 0.1–0.3 mm grind stock.
Can 18KhGT be welded?
With care — weldability is rated fair (40/100). Weldable only before case hardening — preheat 200–300 °C, low-hydrogen filler, post-weld temper; welding a carburized surface causes cracking.
What surface finishes work on 18KhGT?
Not corrosion resistant — protect with oil, manganese/zinc phosphate, black oxide, or Zn/Ni plating (bake to avoid hydrogen embrittlement on hardened parts); shot peening boosts gear-tooth fatigue life.
Can 18KhGT be formed, bent or molded?
Excellent hot forgeability at 1150–1200 °C (stop ≥850 °C) followed by normalizing; cold forming limited, best done in the annealed state.
What is the maximum service temperature of 18KhGT?
18KhGT is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 18KhGT-HR and 18KhGT CARB58?
HR is the default condition — standard mill delivery condition for bar/forging stock — machine, then carburize and harden. CARB58: the service condition for gears, splines and pinions: hard wear-resistant case on a tough core; grind after treatment. Yield strength is 500 MPa in HR versus 1,000 MPa in CARB58.
How much does 18KhGT cost?
18KhGT is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- GOST 4543-2016 Alloy structural steels — grades (18ХГТ) — Rosstandart (2016)
- GB/T 3077-2015 (20CrMnTi) — SAC/China (2015)
- Marochnik steel grade database — 18ХГТ — Marochnik (2023)
- ASM Handbook Vol.1: Properties and Selection — Carburizing Steels — ASM International (1990)
- ASM Handbook Vol.4: Heat Treating (carburizing, case depth and hardness) — ASM International (1991)
- 20CrMnTi / — Mysteel / 1688 (2026)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.