Steel SNC236 QT-35-40HRC
Hardness band
JIS SNC236
QT-35-40HRC = q&T to 35–40 HRC
Maximum practical strength band for small sections; watch the 450–550 °C temper-embrittlement range.
Values for the QT-35-40HRC condition
Other SNC236 tempers and conditions
SNC236 is listed in 9 conditions; see the grade overview at SNC236.
- A
- HR
- N
- CD
- QT
- IH
- QT-25-30HRC
- QT-30-35HRC
- QT-35-40HRC
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest condition — pick it for deep machining, cold straightening or before re-hardening. | 400 | 640 | 26 | 190 HB | — |
Hot rolled | Cheapest mill condition for parts that will be fully heat treated after rough machining. | 420 | 700 | 20 | 16 HRC | 8.2 % IACS |
Normalized | Uniform fine-grain structure for forgings before final Q&T, or for moderately loaded parts. | 520 | 790 | 22 | 20 HRC | — |
Cold drawn | Close-tolerance bright bar for shafts machined without further heat treatment. | 640 | 760 | 14 | 20 HRC | 8 % IACS |
QTDefault Quenched and tempered | Standard supply condition: best strength-to-toughness balance for shafts, axles and bolts. | 700 | 850 | 20 | 24 HRC | — |
Induction hardened | Use when journals or gear teeth need 50+ HRC wear surface over a tough Q&T core. | 750 | 900 | 17 | 54 HRC | 7.2 % IACS |
Q&T to 25–30 HRC | Tough, machinable hardness band for large shafts, couplings and flange bolting. | 760 | 900 | 19 | 27 HRC | — |
Q&T to 30–35 HRC | Higher-strength band for gears and connecting rods where wear and fatigue dominate. | 880 | 1,030 | 16 | 33 HRC | — |
QT-35-40HRCThis page Q&T to 35–40 HRC | Maximum practical strength band for small sections; watch the 450–550 °C temper-embrittlement range. | 1,080 | 1,220 | 13 | 38 HRC | — |
What is SNC236 QT-35-40HRC?
SNC236 QT-35-40HRC is SNC236 heat treated to QT-35-40HRC — maximum practical strength band for small sections; watch the 450–550 °C temper-embrittlement range. SNC236 QT-35-40HRC has a yield strength of 1,080 MPa (157 ksi) and a tensile strength of 1,220 MPa (177 ksi) — stronger than 93% of steel grades. Elongation at break is 13% and the elastic modulus is 205 GPa (29.7 Msi). SNC236 QT-35-40HRC 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). QT is the default condition FabDigit quotes; QT-35-40HRC is available on request or by drawing note.
Advantages
- High strength — 1,080 MPa (157 ksi), better than 93% of steel grades
- Polishes to a fine finish — 65/100, better than 78% of steel grades
Limitations
- Difficult to machine — 33/100, worse than 86% of steel grades
- Limited ductility — 13%, worse than 78% of steel grades
SNC236 QT-35-40HRC properties
Typical room-temperature values for SNC236 QT-35-40HRC; 11 are specific to this condition. Other listed values are SNC236 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
SNC236 QT-35-40HRC 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
SNC236 QT-35-40HRC has a yield strength of 1,080 MPa (157 ksi) and a tensile strength of 1,220 MPa (177 ksi) — stronger than 93% of steel grades. Elongation at break is 13% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
SNC236 QT-35-40HRC is rated for continuous service to 350°C (662 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
SNC236 QT-35-40HRC 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 SNC236 QT-35-40HRC takes about 34 MJ of energy and emits 2.3 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
SNC236 QT-35-40HRC's machinability is poor (33/100, worse than 86% of steel grades); weldability fair (40/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with SNC236 QT-35-40HRC
Is SNC236 easy to machine?
Machines best at 200–260 HB in the Q&T condition with carbide tooling and rigid setups; above 35 HRC expect coated-carbide/CBN finishing and reduced feeds.
Can SNC236 be welded?
Weldable only with care — preheat 200–300 °C, low-hydrogen consumables, and post-weld temper below the last tempering temperature to restore toughness.
Can SNC236 be formed, bent or molded?
Forge at 1050–1200 °C and finish above 850 °C, then normalize; cold forming is limited to mild straightening in the annealed condition.
What surface finishes work on SNC236?
No corrosion resistance of its own — protect with black oxide, phosphate + oil, zinc or hard chrome; grinds and polishes cleanly for bearing journals.
SNC236 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 |
|---|---|---|
| CJIS G4103 | 0.32 – 0.4 | 0.36 |
| Si | 0.15 – 0.35 | 0.25 |
| Mn | 0.5 – 0.8 | 0.65 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Ni | 1 – 1.5 | 1.25 |
| Cr | 0.5 – 0.9 | 0.7 |
| Curesidual max | ≤ 0.3 | — |
| Fe | balance | — |
SNC236 QT-35-40HRC — frequently asked
What is SNC236 QT-35-40HRC used for?
SNC236 QT-35-40HRC is typically used for shafts, gears and bolts. In short: nickel-chromium core toughness; multiple Q&T hardness bands; induction-hardenable journals.
What is the yield strength of SNC236 QT-35-40HRC?
SNC236 QT-35-40HRC has a typical yield strength of 1,080 MPa (157 ksi) and a tensile strength of 1,220 MPa (177 ksi) — stronger than 93% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is SNC236 QT-35-40HRC easy to machine?
Not especially — machinability is rated poor (33/100, worse than 86% of steel grades). Machines best at 200–260 HB in the Q&T condition with carbide tooling and rigid setups; above 35 HRC expect coated-carbide/CBN finishing and reduced feeds.
Can SNC236 QT-35-40HRC be welded?
With care — weldability is rated fair (40/100). Weldable only with care — preheat 200–300 °C, low-hydrogen consumables, and post-weld temper below the last tempering temperature to restore toughness.
What surface finishes work on SNC236 QT-35-40HRC?
No corrosion resistance of its own — protect with black oxide, phosphate + oil, zinc or hard chrome; grinds and polishes cleanly for bearing journals.
Can SNC236 QT-35-40HRC be formed, bent or molded?
Forge at 1050–1200 °C and finish above 850 °C, then normalize; cold forming is limited to mild straightening in the annealed condition.
What is the maximum service temperature of SNC236 QT-35-40HRC?
SNC236 QT-35-40HRC 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 SNC236-QT and SNC236-A?
QT is the default condition — standard supply condition: best strength-to-toughness balance for shafts, axles and bolts. A: softest condition — pick it for deep machining, cold straightening or before re-hardening. Yield strength is 700 MPa in QT versus 400 MPa in A.
Sources
- JIS G4103 Nickel chromium molybdenum / nickel chromium steels — JSA (2018)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4 — Heat Treating — ASM International (1991)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
- SAE J404 Chemical Compositions of SAE Alloy Steels (3140) — SAE International (2009)
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.