1.1133 (20Mn5) Open-Die Forgings Forged bars, seamless rolled rings, shafts, sleeves, discs and blocks made to EN 10250-2 and EN 10269 by Jiangyin Jiangnan Metal Co., Ltd., Jiangsu, China.
1.1133 is the EN material number for the steel grade 20Mn5, a weldable carbon-manganese (non-alloy) constructional steel specified in EN 10269 for components with defined elevated- and low-temperature properties. Its nominal composition is 0.17 to 0.23 % C and 1.00 to 1.50 % Mn. In the normalised (+N) condition it reaches a tensile strength of 490 to 530 MPa depending on section thickness.
1.1133 is used for forged parts in boiler plant, pressure vessels, pipelines and general apparatus construction. Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, manufactures 1.1133 / 20Mn5 forged bars, seamless rolled rings, shafts, sleeves, discs and blocks to customer drawings, supplied with an EN 10204 3.1 inspection certificate.
- EN material number
- 1.1133
- EN steel name
- 20Mn5
- Steel type
- Carbon-manganese, non-alloy constructional steel
- Governing standards
- EN 10269:1999 for composition and properties, EN 10250-2 for open-die forgings
- Nominal composition
- C 0.17 to 0.23 %, Mn 1.00 to 1.50 %, Si max 0.40 %, Al min 0.02 %
- Tensile strength (+N)
- 490 to 530 MPa, by section thickness
- Yield strength (+N)
- 250 to 300 MPa, by section thickness
- Weldability
- Weldable, carbon equivalent CE(IIW) about 0.39 at typical analysis
- Common equivalents
- BS 120M19, AFNOR 20M5, SAE 1022, SAE 1518
- Forms supplied
- Forged bars, hollow bars, sleeves, seamless rolled rings, discs, blocks, gear and pinion shafts
- Manufacturer
- Jiangyin Jiangnan Metal Co., Ltd., Jiangyin, Jiangsu, China
- Enquiries
- sales@steelforgepieces.com, +86 189 2135 9659
What is 1.1133 steel?
1.1133 is a carbon-manganese steel. Its EN chemical designation is 20Mn5. The number comes from the European Werkstoffnummer system, where the leading 1 marks a steel and the 11 group covers non-alloy quality steels. Manganese sits at 1.0 to 1.5 % while carbon stays near 0.20 %. That gives 20Mn5 more strength and better hardenability than a plain 0.2 % carbon steel, without losing weldability or ease of hot working.
The grade appears in EN 10269, the standard covering steels and nickel alloys for fasteners and similar components with specified elevated and low temperature properties. Saarstahl classifies 20Mn5 as a high-temperature constructional steel under DIN EN 10269 and lists its application as a weldable constructional steel for forgings and pipes in boiler plant, and for apparatus, pressure vessel and pipeline construction. The grade was formerly sold under the brand name Atrix 101.
Where 1.1133 forgings are used
- Boiler plant components and pressure-retaining forged parts
- Pressure vessel nozzles, flanges, tube sheets and forged shells
- Pipeline fittings and forged pipe components
- General apparatus and machinery construction where welding is required
- Fasteners and bolting with elevated or low temperature duty under EN 10269
- Medium-strength shafts, sleeves and rings that do not need alloy-steel hardenability
1.1133 (20Mn5) chemical composition
The table below gives the specified composition of steel 20Mn5 / 1.1133 according to EN 10269:1999, in percent by mass. Aluminium carries a minimum rather than a maximum because the grade is supplied fully killed and fine-grain treated. Combined Cr + Mo + Ni is capped at 0.63 % so the steel stays classified as non-alloy.
| C | Si | Mn | P | S | Cr | Mo | Ni | Al | Limit |
|---|---|---|---|---|---|---|---|---|---|
| 0.17 to 0.23 | max 0.40 | 1.00 to 1.50 | max 0.035 | max 0.035 | max 0.40 | max 0.10 | max 0.40 | min 0.02 | Cr+Mo+Ni < 0.63 |
Source: EN 10269:1999. A typical mill analysis quoted by Saarstahl for 20Mn5 is 0.20 % C, 0.50 % Si, 1.15 % Mn.
Carbon equivalent and weldability
Using the IIW formula CE = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15, the typical analysis of 20Mn5 gives a carbon equivalent of about 0.39. That puts 1.1133 in the readily weldable range for thin sections. On heavy forged sections, or where hydrogen pick-up is a risk, apply preheat and control the interpass temperature, and qualify the welding procedure for the actual section thickness. Pressure-retaining welds usually get post-weld heat treatment.
1.1133 (20Mn5) mechanical properties
Normalised condition (+N)
Strength of 1.1133 falls as the ruling section increases, because the cooling rate through the core drops. The values below are minimum specified properties for 20Mn5 in the normalised condition, by nominal thickness.
| Property | to 100 mm | 100 to 250 mm | 250 to 500 mm | 500 to 750 mm |
|---|---|---|---|---|
| Rm, tensile strength (MPa) | 530 | 520 | 500 | 490 |
| Re, upper yield strength (MPa) | 300 | 280 | 260 | 250 |
| A, elongation at fracture, longitudinal (%) | min 22 | |||
| A, elongation at fracture, transverse (%) | min 20 | |||
| Z, reduction of area at fracture (%) | 55 | |||
| KV, impact energy at +20 °C (J) | 55 | |||
Source: EN 10269 property tables for 20Mn5 in the normalised condition.
Quenched and tempered condition (+QT)
Where a higher yield strength is needed, 1.1133 can be supplied quenched and tempered. The values below are the mill-specified properties published by Saarstahl for 20Mn5 in the quenched and tempered delivery condition, by effective wall thickness.
| Property | up to 250 mm | 250 to 500 mm |
|---|---|---|
| Rp0.2, 0.2 % proof stress (MPa) | min 295 | min 275 |
| Rm, tensile strength (MPa) | 490 to 640 | 490 to 640 |
| A5, elongation, longitudinal (%) | min 22 | min 21 |
| A5, elongation, tangential (%) | min 19 | min 18 |
| A5, elongation, transverse (%) | min 15 | min 14 |
| Impact energy DVM, longitudinal (J) | min 48 | min 48 |
| Impact energy DVM, tangential (J) | min 34 | min 34 |
| Impact energy DVM, transverse (J) | min 24 | min 24 |
Source: Saarstahl material specification sheet, 20Mn5, material no. 1.1133.
Heat treatment of 1.1133 forgings
1.1133 is hot formed in the austenitic range, then heat treated to restore grain size and set the final properties. The parameters below are the published mill values for 20Mn5. The cycle for any given forging depends on its section, its geometry and the acceptance criteria written into the order.
| Operation | Temperature | Notes |
|---|---|---|
| Hardening (austenitising) | 870 to 900 °C | Water or polymer quench, depending on section |
| Tempering | 580 to 680 °C | Held to section, then air cooled |
| Normalising | Austenitise, then still-air cool | Standard condition for +N supply |
| Stress relieving | Below the tempering temperature | After heavy machining or welding |
Source: Saarstahl material specification sheet, 20Mn5, material no. 1.1133.
1.1133 equivalent grades and cross-reference
The grades below are the international designations most often cross-referenced against 1.1133 / 20Mn5. Equivalence is approximate. Composition ranges, deoxidation practice and property requirements differ between standards, so a substitute grade has to be confirmed against the design code before use.
| System | Designation | Note |
|---|---|---|
| EN number | 1.1133 | Werkstoffnummer |
| EN name | 20Mn5 | EN 10269 chemical designation |
| Britain (BS) | 120M19 | Nearest BS 970 grade |
| France (AFNOR) | 20M5 | Nearest AFNOR grade |
| USA (SAE / AISI) | 1022, 1518 | Nearest carbon-manganese grades |
| Former trade name | Atrix 101 | Saarstahl brand designation |
Source: Saarstahl material specification sheet for 20Mn5, international steel grades section. Cross-references are for guidance and are not a statement of interchangeability.
1.1133 forged products we manufacture
Jiangyin Jiangnan Metal Co., Ltd. manufactures the following 1.1133 / 20Mn5 forged forms to customer drawings or to standard dimensions. All parts are open-die forged, heat treated, and supplied rough-machined or finish-machined as the order requires.
- Forged barsRound, square, rectangular, flat and hexagonal 1.1133 bars and rods.
- Hollow bars and sleeves1.1133 forged sleeves, bushes, bushings, cylinders, hubs, housings and forged tube.
- Seamless rolled ringsRing-rolled 1.1133 rings for flanges, gear blanks and bearing races.
- Forged ringsMandrel-forged and upset 1.1133 rings where ring rolling is not economic.
- Blocks, discs and plates1.1133 forged blocks, discs, disks and slabs for machining into tooling and structures.
- Shafts1.1133 gear shafts, pinion shafts, spindles and stepped shafts.
- Cases and shells1.1133 forged casings, cases, shells and barrels for apparatus construction.
- Custom forgingsNon-standard 1.1133 forged parts, components and blanks to drawing.
Manufacturing standards, testing and certification
1.1133 forgings can be produced and inspected to the standards below. State the standards and acceptance classes you need on the enquiry so they go into the works order and the inspection plan.
| Standard | Scope |
|---|---|
| EN 10269:1999 | Steels and nickel alloys for fasteners with specified elevated and low temperature properties, the source of the 1.1133 composition and property limits |
| EN 10250-2 | Open die steel forgings for general engineering purposes: non-alloy quality and special steels |
| EN 10204:2004 | Types of inspection document. A 3.1 certificate is issued as standard, 3.2 with third-party witness on request |
| EN 10228-1 | Non-destructive testing of steel forgings, magnetic particle inspection |
| EN 10228-3 | Non-destructive testing of steel forgings, ultrasonic testing of ferritic and martensitic forgings |
| ASTM A388 | Ultrasonic examination of steel forgings, where an ASTM-based inspection report is required |
What is supplied with the parts
- EN 10204 3.1 material test certificate covering heat number, chemical analysis and mechanical test results
- Heat treatment records showing the actual cycle applied
- Dimensional inspection report against the approved drawing
- NDT reports where UT or MPI is specified on the order
- Heat traceability from the ingot or billet through to the finished forging
1.1133 (20Mn5) questions and answers
Is 1.1133 the same as 20Mn5?
Yes. 1.1133 and 20Mn5 are two designations for the same steel. 1.1133 is the EN material number and 20Mn5 is the EN chemical name. Both refer to the carbon-manganese constructional steel specified in EN 10269. Mill certificates usually print both designations together as 20Mn5 / 1.1133.
What is the chemical composition of 1.1133 steel?
Under EN 10269:1999, steel 1.1133 contains 0.17 to 0.23 % carbon, 1.00 to 1.50 % manganese, a maximum of 0.40 % silicon, a maximum of 0.035 % each of phosphorus and sulphur, a maximum of 0.40 % chromium, a maximum of 0.10 % molybdenum, a maximum of 0.40 % nickel and a minimum of 0.02 % aluminium, with Cr + Mo + Ni held below 0.63 %.
What is the tensile strength of 1.1133?
In the normalised condition, 1.1133 has a specified tensile strength of 530 MPa up to 100 mm thickness, 520 MPa from 100 to 250 mm, 500 MPa from 250 to 500 mm and 490 MPa from 500 to 750 mm. Quenched and tempered, the tensile strength is 490 to 640 MPa with a 0.2 % proof stress of at least 295 MPa up to 250 mm effective wall thickness.
Is 1.1133 weldable?
Yes. 1.1133 / 20Mn5 is a weldable constructional steel, used for welded forgings and pipes in boiler plant, pressure vessels and pipelines. Its carbon equivalent at typical analysis is about 0.39 by the IIW formula. Heavy sections need preheat and a qualified welding procedure, and pressure-retaining welds usually get post-weld heat treatment.
What is the American equivalent of 1.1133?
The nearest American designations are SAE 1022 and SAE 1518. Both are carbon-manganese grades with comparable carbon and manganese ranges, but their property requirements and deoxidation practice differ from EN 10269, so any substitution has to be verified against the governing design code.
What heat treatment is applied to 1.1133 forgings?
1.1133 forgings are usually supplied normalised, or hardened from 870 to 900 °C and tempered at 580 to 680 °C when the quenched and tempered condition is specified. Normalising after forging refines the grain structure and gives the +N properties quoted in EN 10269.
What forged shapes can be made from 1.1133?
1.1133 is open-die forged into round, square, rectangular, flat and hexagonal bars, hollow bars, sleeves, bushings, cylinders, hubs and housings, seamless rolled rings, forged rings, blocks, discs, plates, gear shafts, pinion shafts and spindles, along with custom parts made to drawing.
Who manufactures 1.1133 open-die forgings in China?
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, that manufactures 1.1133 / 20Mn5 forged bars, seamless rolled rings, shafts, sleeves, discs and blocks to customer drawings. Enquiries go to sales@steelforgepieces.com or +86 189 2135 9659.
What certification is supplied with 1.1133 forgings?
An EN 10204 3.1 inspection certificate is issued as standard, covering the heat number, chemical analysis and mechanical test results. A 3.2 certificate with third-party witness inspection is available on request, as are ultrasonic testing reports to EN 10228-3 or ASTM A388 and magnetic particle inspection reports to EN 10228-1.
How do I get a price for 1.1133 forgings?
Send the drawing or the finished dimensions, the quantity, the delivery condition (+N or +QT), the certificate type and any NDT or acceptance standards to sales@steelforgepieces.com. Quotations come back within one working day.
Request a quotation for 1.1133 forgings
To price a 1.1133 / 20Mn5 forging accurately we need the following. A drawing in PDF or STEP covers most of it.
- Grade and delivery condition: 1.1133 / 20Mn5, normalised or quenched and tempered
- Finished dimensions or the drawing, and the machining allowance to leave on
- Quantity, and whether the order will repeat
- Certificate type: EN 10204 3.1 or 3.2
- Any NDT, acceptance class or design code that applies
- Destination port and required delivery date
References
- EN 10269:1999, Steels and nickel alloys for fasteners with specified elevated and/or low temperature properties.
- EN 10250-2, Open die steel forgings for general engineering purposes: non-alloy quality and special steels.
- EN 10204:2004, Metallic products: types of inspection documents.
- Saarstahl material specification sheet, 20Mn5, material no. 1.1133: composition, application, heat treatment and quenched-and-tempered properties.
This datasheet is published for guidance. Property values come from the standards and mill data cited above and are not a warranty. Confirm all values against the governing design code and against the material test certificate for the heat actually supplied. Page last reviewed 5 September 2026.