Steel 4615 · temper
Steel 4615 Annealed
Properties of the Annealed condition, compared with the other 4615 tempers.
Pick for maximum softness and machinability before deep cutting, cold forming or carburizing.
What is 4615 Annealed?
4615 Annealed is 4615 in the Annealed temper — pick for maximum softness and machinability before deep cutting, cold forming or carburizing. 4615 Annealed has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 76% of steel grades. Elongation at break is 30% and the elastic modulus is 205 GPa (29.7 Msi). 4615 Annealed 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). HR is the default condition FabDigit quotes; Annealed is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 30%, better than 92% of steel grades
- Forms and bends easily — 65/100, better than 81% of steel grades
Limitations
- Low strength — 340 MPa (49.3 ksi), worse than 76% of steel grades
4615 Annealed properties
Typical room-temperature values for 4615 Annealed — 9 properties are specific to this condition; the rest are grade-level values shared by every 4615 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
4615 Annealed 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).
Mechanical13
4615 Annealed has a yield strength of 340 MPa (49.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 76% of steel grades. Elongation at break is 30% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
4615 Annealed 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 12.3 µm/m·K (6.83 µin/in·°F).
Electrical2
4615 Annealed has an electrical resistivity of 2.3×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 4615 Annealed takes about 29 MJ of energy and emits 2.1 kg of CO₂ — less than 53% of steel grades. Typical recycled content is 30%.
Manufacturability7
4615 Annealed's machinability is good (58/100, better than 75% of steel grades); weldability good (55/100); formability good (65/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 4615 tempers and conditions
4615 is also supplied in 6 other conditions. The full side-by-side table is on the 4615 overview.
- HRDefaultStandard stock form for parts that will be machined and then carburized or heat treated.350 MPa yield · 163 HB
- CarburizedThe intended service condition: hard wear-resistant case over a tough Ni–Mo core for gears and cams.700 MPa yield · 60 HRC
- Q&TDirect hardening of the low-carbon core for tough, moderately strong shafts and pins where no case is required.680 MPa yield · 25 HRC
- CDChoose for as-drawn dimensional accuracy, straightness and higher yield in screw-machine work.540 MPa yield · 192 HB
- NormalizedUse to homogenize forged or hot-worked stock and give a uniform fine-grain core before carburizing.380 MPa yield · 174 HB
- AnnealedPick for maximum softness and machinability before deep cutting, cold forming or carburizing.340 MPa yield · 149 HB
Working with 4615 Annealed
Is 4615 easy to machine?
Machines like other 0.15 %C alloy carburizing steels (~65 % of 1212); normalized stock cuts cleaner than annealed, use sharp tools and positive rake to avoid gumming.
Can 4615 be welded?
Readily arc-welded in the soft condition with low-hydrogen consumables; preheat 100–200 °C on heavy sections and never weld after carburizing.
Can 4615 be formed, bent or molded?
Good cold formability when annealed (bending, upsetting, thread rolling); hot forge 1100–1200 °C and normalize before carburizing.
What surface finishes work on 4615?
No natural corrosion resistance — finish with black oxide, phosphate plus oil, zinc or nickel plating; grind case-hardened surfaces to size after quenching.
4615 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 | 0.16 |
| Mn | 0.45 – 0.65 | 0.55 |
| Si | 0.15 – 0.35 | 0.25 |
| Ni | 1.65 – 2 | 1.82 |
| Mo | 0.2 – 0.3 | 0.25 |
| P | ≤ 0.04 | — |
| S | ≤ 0.04 | — |
| Fe | balance | — |
4615 Annealed — frequently asked
What is 4615 Annealed used for?
4615 Annealed is typically used for gears, forged industrial shafts and pins. In short: carburizing nickel-moly bar.
What is the yield strength of 4615 Annealed?
4615 Annealed has a typical yield strength of 340 MPa (49.3 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 76% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is 4615 Annealed easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machines like other 0.15 %C alloy carburizing steels (~65 % of 1212); normalized stock cuts cleaner than annealed, use sharp tools and positive rake to avoid gumming.
Can 4615 Annealed be welded?
Yes — weldability is rated good (55/100). Readily arc-welded in the soft condition with low-hydrogen consumables; preheat 100–200 °C on heavy sections and never weld after carburizing.
What surface finishes work on 4615 Annealed?
No natural corrosion resistance — finish with black oxide, phosphate plus oil, zinc or nickel plating; grind case-hardened surfaces to size after quenching.
Can 4615 Annealed be formed, bent or molded?
Good cold formability when annealed (bending, upsetting, thread rolling); hot forge 1100–1200 °C and normalize before carburizing.
What is the maximum service temperature of 4615 Annealed?
4615 Annealed 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 4615-HR and 4615-CD?
HR is the default condition — standard stock form for parts that will be machined and then carburized or heat treated. CD: choose for as-drawn dimensional accuracy, straightness and higher yield in screw-machine work. Yield strength is 350 MPa in HR versus 540 MPa in CD.
Can FabDigit make parts in 4615 Annealed?
Yes — 4615 Annealed is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- SAE J404 — Chemical Compositions of SAE Alloy Steels — SAE International (2021)
- ASTM A29/A29M — Steel Bars, Carbon and Alloy, Hot-Wrought — ASTM (2020)
- 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-Mo steels) — ASM International (1991)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
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.