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Steel SNCM625-CD (Cold drawn)

Supply condition

JIS SNCM625

Small-diameter precision bar with better surface and straightness; strength from cold work, low ductility.

Standard cost $$

Values for the CD condition

Other SNCM625 tempers and conditions

SNCM625 is listed in 10 conditions; see the grade overview at SNCM625.

Compare all 10 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Solution annealed
Softest condition for deep machining, hobbing or cold work before final quench and temper.48073022215 HB—
Hot rolled
Mill-supplied stock intended for re-heat-treatment; not for direct load-bearing use.5708801625 HRC7.5 % IACS
Normalized
Uniform fine-grain structure for large forgings before carburizing or final Q&T; note this grade air-hardens strongly.6409301827 HRC7.4 % IACS
CDThis page
Cold drawn
Small-diameter precision bar with better surface and straightness; strength from cold work, low ductility.7008501124 HRC7.5 % IACS
Q&T 28–32 HRC (high-temper, maximum toughness)
Pick when impact toughness and machinability after heat treatment matter more than peak strength.8609902030 HRC7.2 % IACS
QTDefault
Quenched and tempered
Standard supplied condition: ≥940 MPa tensile with high toughness for shafts, large gear blanks and heavy-duty machine parts.8801,0002030 HRC—
Q&T + gas/plasma nitrided
Choose for low-distortion wear and fatigue improvement on finish-machined Q&T parts.8801,0001858 HRC7.2 % IACS
Carburized, hardened and low-temper
For large gears and pins needing a hard wear case over a very tough, deeply hardened Ni-Cr-Mo core.9501,1501260 HRC6.6 % IACS
Q&T 32–36 HRC (medium temper)
Higher-strength gear and shaft condition, still readily machinable and a good nitriding base.9901,1201734 HRC7.2 % IACS
Q&T 36–40 HRC (low temper, high strength)
Near the practical hardness ceiling for this 0.25 % C grade; use where wear and strength dominate and toughness margin is accepted.1,1001,2501438 HRC7.1 % IACS

What is SNCM625-CD?

SNCM625-CD is SNCM625 supplied in the CD condition — small-diameter precision bar with better surface and straightness; strength from cold work, low ductility. SNCM625-CD has a yield strength of 700 MPa (102 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 81% of steel grades. Elongation at break is 11% and the elastic modulus is 206 GPa (29.9 Msi). SNCM625-CD 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; CD is available on request or by drawing note.

Advantages

  • High strength — 700 MPa (102 ksi), better than 81% of steel grades
  • Polishes to a fine finish — 65/100, better than 78% of steel grades

Limitations

  • Limited ductility — 11%, worse than 89% of steel grades
  • Limited formability — 20/100, worse than 80% of steel grades

SNCM625-CD properties

Typical room-temperature values for SNCM625-CD; 22 are specific to this condition. Other listed values are SNCM625 reference data and may not represent this condition. Bars are the position among steel grades.

Physical3

SNCM625-CD 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).

Density7.85 g/cm³0.28 lb/in³
Melting Point (Solidus)1,425°C2,597 °F
Liquidus Temperature1,495°C2,723 °F

Mechanical16

SNCM625-CD has a yield strength of 700 MPa (102 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 81% of steel grades. Elongation at break is 11% and the elastic modulus is 206 GPa (29.9 Msi).

Elastic (Young's) Modulus206 GPa29.9 Msi
Shear Modulus80 GPa11.6 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)850 MPa123 ksi
Yield Strength (0.2% offset)700 MPa102 ksi
Elongation at Break11%
Reduction in Area40%
Compressive Strength710 MPa103 ksi
Shear Strength510 MPa74 ksi
Fatigue Strength (Endurance Limit)390 MPa56.6 ksi
Fracture Toughness (K_IC)75 MPa·√m68.3 ksi·√in
Charpy V-Notch Impact (RT)30 J22.1 ft·lbf
Hardness, Brinell250 HB
Hardness, Rockwell C24 HRC
Hardness, Vickers262 HV

Thermal6

SNCM625-CD is rated for continuous service to 350°C (662 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 69% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).

Thermal Conductivity38 W/m·K22 BTU/hr·ft·°F
Specific Heat Capacity470 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)12.3 µm/m·K6.8 µin/in·°F
Latent Heat of Fusion260 J/g112 BTU/lb
Max Service Temperature (continuous)350°C662 °F
Min Service Temperature-60°C-76 °F

Electrical3

SNCM625-CD conducts electricity at 7.5 % IACS, worse than 67% of steel grades.

Electrical Conductivity7.5 % IACS
Electrical Resistivity2.3×10⁻⁷ Ω·m9.06 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental3

Corrosion resistance is not recommended (13/100), better than 66% of steel grades.

Galvanic Potential (seawater, vs SCE)-0.6 V
Corrosion ResistanceNot recommended13/100
Chemical Resistance SummaryNo inherent corrosion resistance: rusts in humid air and water, attacked by acids and chlorides; requires oil, phosphate, paint, zinc/nickel plating or nitride surface for service.

Sustainability4

Producing a kilogram of SNCM625-CD takes about 34 MJ of energy and emits 2.4 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 30%.

Embodied Energy (primary production)34 MJ/kg14,617 BTU/lb
Embodied Carbon (primary production)2.4 kg CO₂/kg
Embodied Water60 L/kg7.2 gal/lb
Typical Recycled Content30%

Manufacturability7

SNCM625-CD's machinability is fair (50/100, worse than 53% of steel grades); weldability poor (26/100); formability poor (20/100).

MachinabilityFair50/100
Machinability Rating (AISI 1212 = 100 %)55%
WeldabilityPoor26/100
Formability (cold)Poor20/100
Brazeability / SolderabilityFair45/100
PolishabilityGood65/100
Anodizing Responsen/a — ferrous alloy; use nitriding, phosphating, Zn/Ni plating or black oxide instead

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with SNCM625-CD

Is SNCM625 easy to machine?

Machine in the annealed or 28–32 HRC condition with rigid setups, coated carbide, ~80–140 m/min and generous feed; leave grinding stock for post-hardening finishing.

Can SNCM625 be welded?

Poor weldability due to high hardenability — preheat 250–350 °C, use low-hydrogen/matching filler, keep interpass temperature and temper immediately after welding.

Can SNCM625 be formed, bent or molded?

Hot forge 1050–1200 °C with slow controlled cooling (air hardens readily); cold forming limited to mild straightening in the annealed state.

What surface finishes work on SNCM625?

Not anodizable — protect with oil, phosphate, black oxide, zinc or hard-chrome plating; nitriding or induction hardening gives wear resistance, and tempered martensite takes a fine polish.

SNCM625 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.

ElementSpec limit (wt %)Nominal
C0.2 – 0.30.25
Si0.15 – 0.350.25
Mn0.35 – 0.60.48
P≤ 0.03—
S≤ 0.03—
Ni3 – 3.53.25
Cr1 – 1.51.25
Mo0.15 – 0.30.22
Curesidual, max≤ 0.3—
Febalance—

SNCM625-CD — frequently asked

What is SNCM625-CD used for?

SNCM625-CD is typically used for large industrial gears, heavy-duty drive shafts, gear pinions and gear blanks, spline shafts, mill and crane drive components and nitrided wear sleeves. In short: high-hardenability Ni-Cr-Mo steel; heavy-section gear steel; supplied in HRC bands.

What is the yield strength of SNCM625-CD?

SNCM625-CD has a typical yield strength of 700 MPa (102 ksi) and a tensile strength of 850 MPa (123 ksi) — stronger than 81% of steel grades. Strength varies by condition: see the 10 listed tempers.

Is SNCM625-CD easy to machine?

Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machine in the annealed or 28–32 HRC condition with rigid setups, coated carbide, ~80–140 m/min and generous feed; leave grinding stock for post-hardening finishing.

Can SNCM625-CD be welded?

Not readily — weldability is rated poor (26/100). Poor weldability due to high hardenability — preheat 250–350 °C, use low-hydrogen/matching filler, keep interpass temperature and temper immediately after welding.

What surface finishes work on SNCM625-CD?

Not anodizable — protect with oil, phosphate, black oxide, zinc or hard-chrome plating; nitriding or induction hardening gives wear resistance, and tempered martensite takes a fine polish.

Can SNCM625-CD be formed, bent or molded?

Hot forge 1050–1200 °C with slow controlled cooling (air hardens readily); cold forming limited to mild straightening in the annealed state.

What is the maximum service temperature of SNCM625-CD?

SNCM625-CD 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 SNCM625-QT and SNCM625-A?

QT is the default condition — standard supplied condition: ≥940 MPa tensile with high toughness for shafts, large gear blanks and heavy-duty machine parts. A: softest condition for deep machining, hobbing or cold work before final quench and temper. Yield strength is 880 MPa in QT versus 480 MPa in A.

Sources

  1. JIS G4103 — Nickel-chromium-molybdenum steels — Japanese Standards Association (2019)
  2. ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
  3. ASM Handbook Vol.4 — Heat Treating — ASM International (1991)
  4. Machinery's Handbook, 31st ed. (machinability and heat-treat data) — Industrial Press (2020)

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.