Steel SNC415-HR (Hot rolled)
Supply condition
JIS SNC415
Cheapest mill condition for forging stock or parts that will be fully heat treated later.
Values for the HR condition
Other SNC415 tempers and conditions
SNC415 is listed in 8 conditions; see the grade overview at SNC415.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Softest condition, used when the part is cold headed, cold extruded or deep-formed before carburizing. | 360 | 570 | 30 | 155 HB | 7.2 % IACS |
ADefault Solution annealed | Standard stocked/soft condition for machining gear blanks before carburizing. | 420 | 640 | 25 | 170 HB | — |
HRThis page Hot rolled | Cheapest mill condition for forging stock or parts that will be fully heat treated later. | 460 | 700 | 21 | 14 HRC | 7 % IACS |
Normalized | Grain-refined, more uniform condition for forgings prior to machining and carburizing. | 510 | 760 | 20 | 17 HRC | 7 % IACS |
Cold drawn | Bright, close-tolerance bar for automatic-lathe parts (pins, small shafts) that are later carburized. | 660 | 790 | 12 | 21 HRC | 7 % IACS |
Quenched and tempered | Use when the JIS G 4053 core mechanical requirements (≥780 MPa) must be certified, or for uncarburized through-hardened parts. | 660 | 850 | 19 | 26 HRC | — |
Carburized, quenched and low-temperature tempered | Final service condition for gears and splines: hard 58–62 HRC case over a tough ~30–40 HRC core. | 780 | 1,050 | 12 | 60 HRC | — |
Carburized, hardened and shot peened | Pick for highly loaded transmission gears where root bending fatigue governs; peening adds compressive residual stress. | 900 | 1,150 | 10 | 60 HRC | 6.5 % IACS |
What is SNC415-HR?
SNC415-HR is SNC415 supplied in the HR condition — cheapest mill condition for forging stock or parts that will be fully heat treated later. SNC415-HR has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 55% of steel grades. Elongation at break is 21% and the elastic modulus is 205 GPa (29.7 Msi). SNC415-HR 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). A is the default condition FabDigit quotes; HR is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 65/100, better than 78% of steel grades
SNC415-HR properties
Typical room-temperature values for SNC415-HR; 23 are specific to this condition. Other listed values are SNC415 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
SNC415-HR 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
SNC415-HR has a yield strength of 460 MPa (66.7 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 55% of steel grades. Elongation at break is 21% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
SNC415-HR is rated for continuous service to 400°C (752 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 56% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
SNC415-HR conducts electricity at 7 % IACS, worse than 74% of steel grades.
Chemical & Environmental2
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of SNC415-HR takes about 30 MJ of energy and emits 2.1 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 30%.
Manufacturability7
SNC415-HR's machinability is fair (50/100, worse than 53% of steel grades); weldability good (55/100); formability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with SNC415-HR
Is SNC415 easy to machine?
Machine soft (annealed ~170 HB) with carbide at moderate speed and generous feed; the gummy Ni-bearing matrix smears at low feeds, and after carburizing only grinding/hard-turning with CBN is practical.
Can SNC415 be welded?
Low carbon makes it weldable with low-hydrogen electrodes, but Ni-Cr hardenability calls for 150–250 °C preheat and post-weld stress relief; never weld a carburized surface.
Can SNC415 be formed, bent or molded?
Good hot forging at 1100–1200 °C followed by normalizing; cold heading and upsetting are feasible in the spheroidize-annealed condition.
What surface finishes work on SNC415?
Carburize 900–930 °C, oil quench, temper 150–200 °C, then grind; protect with phosphate + oil, black oxide, zinc or Ni plating (bake after plating to avoid hydrogen embrittlement).
SNC415 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 | 0.12 – 0.18 | 0.15 |
| Si | 0.15 – 0.35 | 0.25 |
| Mn | 0.35 – 0.65 | 0.5 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Ni | 2 – 2.5 | 2.25 |
| Cr | 0.2 – 0.5 | 0.35 |
| Curesidual, max | ≤ 0.3 | — |
| Fe | balance | — |
SNC415-HR — frequently asked
What is SNC415-HR used for?
SNC415-HR is typically used for transmission and reduction gears, pinion and drive shafts, splined shafts, gear pump shafts, cam followers and rollers and machine tool spindles. In short: tougher core than Cr grades; nickel-chromium carburizing steel; good cold-heading stock.
What is the yield strength of SNC415-HR?
SNC415-HR has a typical yield strength of 460 MPa (66.7 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 55% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is SNC415-HR easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machine soft (annealed ~170 HB) with carbide at moderate speed and generous feed; the gummy Ni-bearing matrix smears at low feeds, and after carburizing only grinding/hard-turning with CBN is practical.
Can SNC415-HR be welded?
Yes — weldability is rated good (55/100). Low carbon makes it weldable with low-hydrogen electrodes, but Ni-Cr hardenability calls for 150–250 °C preheat and post-weld stress relief; never weld a carburized surface.
What surface finishes work on SNC415-HR?
Carburize 900–930 °C, oil quench, temper 150–200 °C, then grind; protect with phosphate + oil, black oxide, zinc or Ni plating (bake after plating to avoid hydrogen embrittlement).
Can SNC415-HR be formed, bent or molded?
Good hot forging at 1100–1200 °C followed by normalizing; cold heading and upsetting are feasible in the spheroidize-annealed condition.
What is the maximum service temperature of SNC415-HR?
SNC415-HR is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between SNC415-A and SNC415 CHT-SP?
A is the default condition — standard stocked/soft condition for machining gear blanks before carburizing. CHT-SP: pick for highly loaded transmission gears where root bending fatigue governs; peening adds compressive residual stress. Yield strength is 420 MPa in A versus 900 MPa in CHT-SP.
Sources
- JIS G 4053 — Low-alloyed steels for machine structural use — Japanese Industrial Standards Committee (2016)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4 — Heat Treating (carburizing of Ni-Cr steels) — ASM International (1991)
- ASM Handbook Vol.16 — Machining (machinability ratings of alloy steels) — ASM International (1989)
- SAE J404 — Chemical Compositions of SAE Alloy Steels (3115/3310 reference) — 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.