CS · carbon steel
Carbon Steel 1020
Effectively 1018 with a slightly tighter carbon range. Same machining behaviour, same need for a protective finish.
Quoting this material
- Typical lead time
- 5–10 working days
- Condition
- As-rolled, normalised, or cold drawn
- Achievable finish
- Ra 1.6 µm typical · Ra 0.4 µm best
Machined in-house to your drawing: see the precision CNC machining service and the machine and inspection capability it runs on.
Machinability
Our own 1–10 shop ranking, not a published index: 10 is free-cutting brass C360, 1 is Inconel 718. It ranks how a material behaves on the floor - cycle time, chip control and tool life together. Where a published index exists it is quoted in the note.
Effectively 1018 with a slightly tighter carbon range. Same machining behaviour, same need for a protective finish.
Properties as supplied
| Parameter | Value | Unit |
|---|---|---|
| Tensile strength | 420 | MPa |
| Yield strength | 350 | MPa |
| Elongation | 18 | % |
| Hardness | 143 | HB |
| Thermal conductivity | 51.9 | W/m·K |
| Modulus of elasticity | 205 | GPa |
Hardness, tensile and thermal figures are typical published values for the condition stated. Actual mill certificates govern; send the specification with the drawing and we confirm against the certificate before the material is cut.
Condition
As-rolled, normalised, or cold drawn
Heat treatment
Case carburisable rather than through-hardenable, like 1018. Where a hard skin is needed it is a carburise-and-harden job, not a straight quench.
Achievable surface finish
Ra 1.6 µm
Ra 0.4 µm
Finishes well; plating or black oxide is expected on anything going into service unprotected.
Tooling and cutting parameters
Cutting speed
- 150–300 m/min (carbide)
Feed
- 0.15–0.35 mm/rev turning · 0.10–0.25 mm/tooth milling
Tooling
- Coated or uncoated carbide
Coolant
- Flood or mist
Starting points for carbide on a rigid setup, not a guarantee. The right numbers depend on the machine, the toolholder and the fixturing - ask and we will say what we would actually run.
Typical applications
- Weld frames and bases
- Hydraulic cylinder components
- Coupling and adapter bodies
- Machined weld bosses
- General fabrication hardware
DFM notes for this grade
- Almost always present because a specification names it, not because it behaves differently from 1018 - do not switch without checking the drawing
- Weldable with any common process, which is the real reason it shows up on fabricated assemblies
- Its 0.2% carbon is close to the carburising sweet spot: case hardness comes up quickly and the core stays tough
Questions buyers ask
- Is 1020 a straight substitute for 1018?
- For a machined part, functionally yes. On a controlled drawing, no - the specification names an alloy and a heat treatment, and substituting means re-approving. Send what the drawing says and we will machine that.
- What should be quoted for a 1020 part that has to resist wear?
- A carburised case, not a harder alloy. Case depth and surface hardness belong on the drawing; a 1020 part with a 0.8 mm case at 60 HRC wears far better than a 1045 part hardened through, and it stays tough underneath.