Steel C35RC +A (Annealed)
Heat-treated state
AISI/SAE 1035 · EN C35, 1.1060 · JIS S35C · GB 35
Lowest-hardness state for heavy machining or as a starting point before quench-and-temper.
Values for the +A condition
Other C35RC tempers and conditions
C35RC is listed in 8 conditions; see the grade overview at C35RC.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
+ACDefault Spheroidize annealed | Standard cold-heading delivery state: spheroidized cementite gives maximum upsetting ductility at low hardness. | 300 | 520 | 25 | 150 HB | 51 W/m·K |
+AThis page Annealed | Lowest-hardness state for heavy machining or as a starting point before quench-and-temper. | 300 | 530 | 24 | 155 HB | 10.5 % IACS |
Hot rolled | Cheapest delivery state for parts that will be re-heat-treated or only lightly machined. | 340 | 600 | 18 | 175 HB | — |
Normalized | Uniform fine ferrite-pearlite for general engineering bar; good machining and predictable response to later hardening. | 340 | 580 | 20 | 170 HB | — |
Quenched and tempered | Balanced strength/toughness condition for shafts, pins and studs after machining. | 420 | 660 | 19 | 16 HRC | 48 W/m·K |
Spheroidize annealed and cold drawn | Drawn-to-size wire/bar for multi-station cold heading and turned parts: close tolerance, bright surface, higher strength than +AC. | 500 | 590 | 12 | 178 HB | — |
Cold drawn | Straight cold-drawn bar for machined shafts and pins where drawn strength and tolerance, not headability, matter. | 550 | 650 | 10 | 192 HB | — |
Hardenability-controlled, supplied hardened and tempered | Pick when parts (e.g. class 8.8 fasteners) are quench-hardened after forming and a guaranteed Jominy band is required. | 620 | 800 | 15 | 23 HRC | — |
What is C35RC +A?
C35RC +A is C35RC heat treated to +A — lowest-hardness state for heavy machining or as a starting point before quench-and-temper. C35RC +A has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 86% of steel grades. Elongation at break is 24% and the elastic modulus is 205 GPa (29.7 Msi). C35RC +A 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). +AC is the default condition FabDigit quotes; +A is available on request or by drawing note.
Advantages
- Conducts heat well — 52 W/m·K (30 BTU/hr·ft·°F), better than 98% of steel grades
- High electrical conductivity — 10.5 % IACS, better than 89% of steel grades
- Forms and bends easily — 72/100, better than 88% of steel grades
Limitations
- Low strength — 300 MPa (43.5 ksi), worse than 86% of steel grades
- Low fracture toughness — 62 MPa·√m (56.4 ksi·√in), worse than 76% of steel grades
C35RC +A properties
Typical room-temperature values for C35RC +A; 22 are specific to this condition. Other listed values are C35RC reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
C35RC +A 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
C35RC +A has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 86% of steel grades. Elongation at break is 24% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
C35RC +A is rated for continuous service to 400°C (752 °F). It conducts heat at 52 W/m·K (30 BTU/hr·ft·°F), better than 98% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
C35RC +A conducts electricity at 10.5 % IACS, better than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of C35RC +A takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 28%.
Manufacturability7
C35RC +A's machinability is good (55/100, better than 62% of steel grades); weldability good (58/100); formability very good (72/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with C35RC +A
Is C35RC easy to machine?
Machines readily at ~65 % of 1212; spheroidized (+AC) stock can smear — prefer normalized or cold-drawn bar and sharp coated carbide with generous feed.
Can C35RC be welded?
Weldable with care (CE ≈ 0.5): use low-hydrogen consumables, 150–250 °C preheat on sections over ~20 mm and slow cooling to avoid HAZ martensite cracking.
Can C35RC be formed, bent or molded?
In +AC or +AC+C condition it cold-heads, upsets and thread-rolls well; hot forge at 1100–850 °C, then normalize before final machining.
What surface finishes work on C35RC?
No anodizing; protect with zinc or zinc-nickel plating (bake for hydrogen embrittlement above ~320 HV), phosphate + oil, black oxide or paint; polishes to a fair bright finish.
C35RC 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 | 0.32 – 0.39 | 0.35 |
| Sikept low for cold-heading quality | ≤ 0.3 | 0.2 |
| Mn | 0.5 – 0.8 | 0.65 |
| P | ≤ 0.03 | — |
| S'R' = specified sulfur range for machinability | 0.02 – 0.04 | 0.03 |
| Crresidual | ≤ 0.3 | — |
| Niresidual | ≤ 0.3 | — |
| Curesidual | ≤ 0.25 | — |
| Moresidual | ≤ 0.1 | — |
| Fe | balance | — |
C35RC +A — frequently asked
What is C35RC +A used for?
C35RC +A is typically used for shafts, bolts, gears, axles and machine components. In short: balanced strength and machinability; general-purpose engineering bar; weldable only with preheat.
What is the yield strength of C35RC +A?
C35RC +A has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 530 MPa (76.9 ksi) — weaker than 86% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is C35RC +A easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machines readily at ~65 % of 1212; spheroidized (+AC) stock can smear — prefer normalized or cold-drawn bar and sharp coated carbide with generous feed.
Can C35RC +A be welded?
Yes — weldability is rated good (58/100). Weldable with care (CE ≈ 0.5): use low-hydrogen consumables, 150–250 °C preheat on sections over ~20 mm and slow cooling to avoid HAZ martensite cracking.
What surface finishes work on C35RC +A?
No anodizing; protect with zinc or zinc-nickel plating (bake for hydrogen embrittlement above ~320 HV), phosphate + oil, black oxide or paint; polishes to a fair bright finish.
Can C35RC +A be formed, bent or molded?
In +AC or +AC+C condition it cold-heads, upsets and thread-rolls well; hot forge at 1100–850 °C, then normalize before final machining.
What is the maximum service temperature of C35RC +A?
C35RC +A 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.
Sources
- EN 10263-2 — Steel rod, bars and wire for cold heading and cold extrusion: non-heat-treatable steels — CEN (2017)
- EN 10263-4 — Steels for quenching and tempering (cold heading) — CEN (2017)
- EN 10083-2 — Steels for quenching and tempering: non-alloy steels (C35, C35R) — CEN (2006)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
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.