Steel SCr415
JIS SCr415
SCr415 is a JIS low-carbon chromium carburizing steel (5115, 15Cr) used for Japanese-standard automotive and machinery gears, filling the same role as EN 20Cr4-class grades.
Reference datasheet — SCr415 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 A condition
SCr415 tempers and conditions
SCr415 is supplied in 8 conditions, soft to hard. A is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Choose for cold-headed or cold-extruded gear and fastener blanks needing maximum ductility. | 300 | 480 | 31 | 140 HB | 8 % IACS |
ADefault Solution annealed | Standard stocked condition: soft and dimensionally stable for machining gear blanks before carburizing. | 340 | 540 | 26 | 160 HB | — |
Hot rolled | Cheapest mill condition for bar that will be forged or fully heat treated afterwards. | 400 | 600 | 21 | 180 HB | — |
Normalized | Used to refine forging structure and give uniform grain size before carburizing. | 420 | 620 | 23 | 180 HB | 7.8 % IACS |
Carbonitrided and tempered | Use for small, low-load gears, washers and levers where a 0.1–0.4 mm hard, wear-resistant case is enough. | 520 | 750 | 18 | 59 HRC | 7.5 % IACS |
Cold drawn | Pick for close-tolerance bright bar for pins, shafts and small gear blanks with minimal turning. | 580 | 710 | 12 | 210 HB | — |
Carburized, quenched and tempered | The service condition for gears and splines: 0.6–1.2 mm effective case at 58–62 HRC over a tough core. | 640 | 900 | 17 | 60 HRC | — |
Quenched and tempered | For small, thin parts that need a hard through-section rather than a carburized case. | 760 | 1,000 | 13 | 32 HRC | — |
What is SCr415?
SCr415 is a JIS low-carbon chromium carburizing steel (5115, 15Cr) used for Japanese-standard automotive and machinery gears, filling the same role as EN 20Cr4-class grades. Supplied as bar, forging stock and cold-drawn stock, it machines and cold-forms well in the soft condition (annealed 143–187 HB, machinability score 60, formability 60), then carburizes to a hard case over a tough core; the soft-condition properties are about 340 MPa yield, 540 MPa tensile and 26 % elongation at 160 HB. Service is limited to about 350 °C, there is no corrosion resistance, and hardenability is modest — SCM415 or SCM425 are the alternatives for deeper case and higher core strength in thick sections. SCr415 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). SCr415 has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 76% of steel grades. Elongation at break is 26% and the elastic modulus is 206 GPa (29.9 Msi).
What is SCr415 used for?
- carburized gears
- shafts
- pins
Advantages
- Ductile — tolerates forming and impact — 26%, better than 82% of steel grades
Limitations
- Low strength — 340 MPa (49.3 ksi), worse than 76% of steel grades
SCr415 properties
Typical room-temperature values for SCr415-A; bars are the position among steel grades.
Physical3
SCr415 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).
Mechanical15
SCr415 has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 76% of steel grades. Elongation at break is 26% and the elastic modulus is 206 GPa (29.9 Msi).
Thermal6
SCr415 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 11.9 µm/m·K (6.61 µin/in·°F).
Electrical3
SCr415 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 SCr415 takes about 27 MJ of energy and emits 2 kg of CO₂ — less than 59% of steel grades. Typical recycled content is 30%.
Manufacturability7
SCr415's machinability is good (60/100, better than 83% of steel grades); weldability good (60/100); formability good (60/100).
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. SCr415 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with SCr415
Is SCr415 easy to machine?
Machine soft (annealed 143–187 HB) with carbide or HSS at ~65 % of 1212 rates; leave 0.1–0.3 mm stock for post-carburizing grinding since the 60 HRC case needs CBN/grinding.
Can SCr415 be welded?
Weldable in the soft condition with low-hydrogen consumables, 150–250 °C preheat and post-weld stress relief; do not weld carburized surfaces (cracking and case softening).
Can SCr415 be formed, bent or molded?
Good hot forgeability at 1100–1200 °C; cold heading and extrusion practical after spheroidize annealing plus phosphate/soap lubrication; normalize before carburizing to control distortion.
SCr415 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 | 0.13 – 0.18 | 0.15 |
| Si | 0.15 – 0.35 | 0.25 |
| Mn | 0.6 – 0.9 | 0.75 |
| P | ≤ 0.03 | |
| S | ≤ 0.03 | |
| Cr | 0.9 – 1.2 | 1.05 |
| Niresidual, max | ≤ 0.25 | |
| Curesidual, max | ≤ 0.3 | |
| Fe | balance |
What surface finishes work on SCr415?
No anodizing (ferrous) — protect with oil, manganese phosphate, black oxide, or zinc/nickel plating (bake to avoid hydrogen embrittlement of the hardened case); ground and shot-peened gear flanks give best 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 SCr415 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- 511515Cr
How much does SCr415 cost?
SCr415 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.
SCr415 — frequently asked
What is SCr415 used for?
SCr415 is typically used for carburized gears, shafts and pins. In short: entry-level carburizing chrome steel; good soft-state machinability; 5115 / 15Cr equivalent.
What is the yield strength of SCr415?
SCr415 has a typical yield strength of 340 MPa (49.3 ksi) and a tensile strength of 540 MPa (78.3 ksi) — weaker than 76% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is SCr415 easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Machine soft (annealed 143–187 HB) with carbide or HSS at ~65 % of 1212 rates; leave 0.1–0.3 mm stock for post-carburizing grinding since the 60 HRC case needs CBN/grinding.
Can SCr415 be welded?
Yes — weldability is rated good (60/100). Weldable in the soft condition with low-hydrogen consumables, 150–250 °C preheat and post-weld stress relief; do not weld carburized surfaces (cracking and case softening).
What surface finishes work on SCr415?
No anodizing (ferrous) — protect with oil, manganese phosphate, black oxide, or zinc/nickel plating (bake to avoid hydrogen embrittlement of the hardened case); ground and shot-peened gear flanks give best fatigue life.
Can SCr415 be formed, bent or molded?
Good hot forgeability at 1100–1200 °C; cold heading and extrusion practical after spheroidize annealing plus phosphate/soap lubrication; normalize before carburizing to control distortion.
What is the maximum service temperature of SCr415?
SCr415 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 SCr415-A and SCr415-QT?
A is the default condition — standard stocked condition: soft and dimensionally stable for machining gear blanks before carburizing. QT: for small, thin parts that need a hard through-section rather than a carburized case. Yield strength is 340 MPa in A versus 760 MPa in QT.
How much does SCr415 cost?
SCr415 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
- JIS G 4053 — Low-alloyed steels for machine structural use — JISC (2016)
- GB/T 3077 — Alloy structural steels (15Cr) — SAC (2015)
- SAE J404 / ASTM A29 (5115 chemical limits) — SAE / ASTM (2020)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4A — Steel Heat Treating Fundamentals and Processes (carburizing) — ASM International (2013)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
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.