230M07 Steel at a Glance
- Grade
- 230M07, the BS 970 free-cutting (resulphurised) low-carbon steel grade; closely equivalent to the popular EN1A.
- Nominal composition
- C 0.15% max, Mn 0.90–1.30%, S 0.25–0.35% (added for machinability), Si 0.05% max, P 0.090% max.
- Equivalents
- EN1A (closest) · AISI 1213 · EN 11SMn30 / 1.0715 · JIS SUM22 / SUM23.
- Machinability
- The free-cutting benchmark: manganese-sulphide inclusions break the chip and speed the cut.
- Product forms
- Bright bars, hexagons and rounds.
- Typical uses
- CNC-turned components, fasteners, studs, pins, bushes, couplings and fittings.
- Supply & MOQ
- Cold drawn (bright), turned & polished or hot rolled. MOQ 5 MT per size; 5–6 m or cut-to-length.
What is 230M07 steel?
230M07 is the British Standard (BS 970) designation for a free-cutting, resulphurised low-carbon steel, closely equivalent to the grade most buyers call EN1A. In the BS 970 code, the letter "M" shows the steel is supplied to specified mechanical-property requirements, and the final "07" denotes a mean carbon content of about 0.07%. EN1A is the more popular name in the trade, but the two are not an identical specification.
Treat EN1A as the nearest equivalent rather than the same steel. 230M07 (BS 970-3) caps carbon at 0.15% with no lower limit and runs slightly higher manganese (0.90–1.30%) and sulphur (0.25–0.35%), whereas EN1A is usually specified at 0.07–0.15% carbon, 0.80–1.20% manganese and 0.20–0.30% sulphur. For most turned-part applications the two are interchangeable, but a drawing calling for 230M07 should be supplied to the BS 970 230M07 limits and certified on the mill test certificate.
What makes 230M07 free-cutting is sulphur. Ordinary low-carbon steel keeps sulphur low; in this grade it is added deliberately and, with the high manganese, forms manganese-sulphide (MnS) inclusions through the bar. During turning, those inclusions break the chip into short pieces, cut tool friction, and leave a clean finish, so the steel machines faster and with longer tool life than any plain-carbon grade.
The trade-offs are strength, weldability and finishing. With carbon capped at 0.15%, 230M07 is soft and does not respond to through-hardening, and the high sulphur makes it a poor choice for structural welding and unsuitable for hot-dip galvanising. It can, however, be carburised to add a wear-resistant case. Buyers choose it for one reason: machinability first. Where a turned part also needs medium-carbon strength, the free-cutting answer is EN8M.
230M07 chemical composition
The composition below is the BS 970-3 specification for 230M07. The defining features are the deliberately high sulphur and the supporting manganese, both there to make the steel free-cutting. 230M07 is supplied as a balanced (semi-killed) quality, and the exact heat analysis is confirmed on the mill test certificate.
| Element | Range (%) | Role |
|---|---|---|
| Carbon (C) | 0.15 max | Low — keeps the steel soft and easy to cut |
| Silicon (Si) | 0.05 max | Kept low — 230M07 is a balanced, not fully killed, quality |
| Manganese (Mn) | 0.90 – 1.30 | Combines with sulphur to form chip-breaking MnS |
| Sulphur (S) | 0.25 – 0.35 | Added on purpose — the free-cutting element |
| Phosphorus (P) | 0.090 max | Slightly raised; aids finish and chip break |
Composition to BS 970-3. Free-cutting grades intentionally carry higher S and P than structural steels; the exact heat analysis is certified on the MTC.
230M07 mechanical and physical properties
230M07 is supplied most often as cold-drawn (bright) bar, which raises strength over the as-rolled condition through work hardening. BS 970-3 specifies the mechanical properties as minimum values that vary with bar diameter — smaller bars are drawn harder and carry higher strength. The table below lists those specified minimums for the cold-drawn condition; guaranteed values are stated on the mill test certificate.
| Bar diameter (mm) | Tensile Rm (N/mm², min) | 0.2% proof Rp0.2 (N/mm², min) | Elongation A (%, min) |
|---|---|---|---|
| 6 – 13 | 480 | 360 | 6 |
| over 13 – 16 | 460 | 345 | 7 |
| over 16 – 40 | 430 | 300 | 8 |
| over 40 – 63 | 390 | 240 | 9 |
| over 63 – 76 | 370 | 225 | 10 |
In the hot-rolled and turned (or ground) condition, 6–100 mm, the minimums are Rm 360 N/mm², yield 215 N/mm² and elongation 22%, at about 103 HB. Cold-drawn bar runs harder — typically around 126–180 HB — though BS 970-3 does not specify a hardness for the cold-drawn condition. Values are confirmed on the MTC.
Physical properties
| Property | Typical value |
|---|---|
| Density | 7.85 g/cm³ |
| Modulus of elasticity | ≈ 200 GPa |
| Thermal conductivity | ≈ 50 W/m·K |
| Coefficient of thermal expansion | ≈ 11–12 × 10⁻⁶ /K |
| Specific heat capacity | ≈ 470 J/kg·K |
Physical constants are representative of low-carbon free-cutting steel and are largely independent of supply condition.
What is 230M07 equivalent to?
230M07 is a BS 970 grade in its own right. The nearest grades in the major standards are listed below; they match on free-machinability and low carbon, but exact sulphur ranges and tramp-element limits differ between standards, so always confirm against the heat analysis on the MTC.
| Standard / Region | Designation |
|---|---|
| BS 970 (UK) | 230M07 — this grade |
| EN designation (UK) | EN1A — popular equivalent name (limits differ slightly) |
| AISI / SAE (USA) | 1213 |
| EN / DIN (Europe) | 11SMn30 / 9SMn28 — material no. 1.0715 |
| JIS (Japan) | SUM22, SUM23 |
If you are cross-referencing from EN1A, our reference page for EN1A steel on the main Ambhe Ferro site covers the closest equivalent grade.
Can 230M07 be heat treated?
230M07 is not a through-hardening grade. With carbon capped at 0.15%, there is not enough carbon to develop useful hardness by quenching, so the steel is supplied and used in the soft, machinable condition. It can be carburised to add a hard, wear-resistant case where a component needs one; for a fully hardenable part, select a dedicated case-hardening grade such as 16MnCr5.
| Operation | Guidance |
|---|---|
| Forging | 1100 – 1280 °C |
| Through-hardening | Not applicable — carbon too low |
| Carburising | Possible to add a wear-resistant case where required |
| Stress relief | Possible after heavy machining if dimensional stability matters |
The high free-cutting sulphur content limits weldability and cold forming, and the grade is not suitable for hot-dip galvanising.
What sizes and forms of 230M07 are available?
Free-cutting steel is bought mainly as bright bar and hexagon, because the parts made from it are turned and threaded. Ambhe Ferro supplies 230M07 across the following forms and sizes; non-standard sizes are frequently available make-to-order.
Bright Bars
Hexagons
Rounds
Custom & cut lengths
Applications of 230M07
230M07 is the default grade wherever the priority is machining a large quantity of small components economically, and the working load is modest. Typical uses include:
- High-volume CNC and auto-lathe (capstan / sliding-head) turned components
- Fasteners — studs, bolts, screws, nuts, threaded rod
- Pins, dowels, bushes, spacers and collars
- Hydraulic and pneumatic fittings, adaptors and couplings
- Electrical hardware, connector bodies and instrument parts
- General-purpose machined components with low stress and no hardening requirement
Where a turned part also needs to carry a working load or be hardened, step up to a free-cutting medium-carbon grade. See the 230M07 vs EN8M comparison below.
Why source 230M07 from Ambhe Ferro
- We roll it, we don't just stock it. Heat-to-heat consistency from our own rolling mill and bright-bar lines.
- ISO 9001 certified with an in-house QC laboratory testing every heat.
- Heat-wise mill test certificate on every dispatch; third-party inspection (SGS, BV, TÜV) on request.
- Multiple supply conditions — hot rolled, bright (cold drawn), turned & polished.
- Over 39 years serving the Mumbai–Pune–Nashik corridor in Maharashtra, with quick dispatch from locations near JNPT.
How to order 230M07
Tell us the form, size, condition and tonnage, and we respond with price, availability and lead time, plus a mill test certificate on every heat.
| Item | Detail |
|---|---|
| Forms | Bright bars, hexagons, rounds |
| Conditions | Hot rolled, cold drawn (bright), turned & polished |
| Minimum order | 5 MT per size (smaller via approved stockists) |
| Length | 5–6 m standard; cut-to-length on request |
| Documentation | Heat-wise mill test certificate; third-party inspection on request |
230M07 steel — frequently asked questions
What is 230M07 steel?
Is 230M07 the same as EN1A?
What is the chemical composition of 230M07?
What is 230M07 equivalent to?
Can 230M07 be hardened or heat treated?
What is 230M07 used for?
Why does 230M07 machine so well?
Where can I buy 230M07 steel in India?
What is the minimum order, and is a mill test certificate provided?
Let's Talk 230M07
Tell us your grade, form, size, and tonnage. We'll respond with pricing, availability, and lead time — and a mill test certificate on every heat.