EN S235JR steel

Designation and governing standard

Saarstahl's June 2024 S235JR wide-flat declaration gives 235 MPa minimum yield through 16 mm and 225 MPa above 16 through 40 mm. An 18 mm wide flat uses the 225 MPa row. JR denotes 27 J Charpy impact energy at +20°C. The test temperature leaves component service temperature to the design assessment. Saarstahl declared performance, Tata grade designation guide

S235JR is a non-alloy structural steel designation associated with EN 10025-2 and material number 1.0038. DIN Media identifies DIN EN 10025-2:2019-10, the German adoption of EN 10025-2:2019, as current. Its title covers technical delivery conditions for hot-rolled non-alloy structural steels. Keep the national adoption, edition, product form and delivery condition in the material record. DIN Media, standard listing; Saarstahl, S235JR wide-flat declaration

The number 235 is not a yield-strength promise at every thickness. “JR” concerns impact toughness, not strength or surface finish. Tata Steel's training material decodes JR as Charpy impact energy 27 J at +20°C, J0 as 27 J at 0°C and J2 as 27 J at −20°C. These are distinct toughness classes; removing the suffix loses important information. Tata Steel, steel grades, designation slide

Do not equate the grade automatically with ASTM A36, a historical St designation or another S235 product. Similar room-temperature strength does not establish matching chemistry, test requirements, inspection documents or service suitability. A hollow-section designation also needs its applicable product standard; Tata's guidance distinguishes EN 10210 hot-finished and EN 10219 cold-formed structural hollow sections. Tata Steel, product standards

Bounded wide-flat property example

Saarstahl's declaration for S235JR wide flat steel, signed June 28, 2024, lists these minimum yield strengths by nominal thickness:

Its tensile ranges are 360–510 MPa for 3 < t ≤ 100 mm, 350–500 MPa for 100 < t ≤ 150 mm, and 340–490 MPa for 150 < t ≤ 200 mm. These are declared values for that product, not a complete acceptance table for every plate, strip or section sold as S235JR. Saarstahl, declared performance, page 2

For a labeled illustration, a 12 mm item falls in the 235 MPa row, while a 25 mm item falls in the 225 MPa row. The difference is 235 − 225 = 10 MPa, approximately 10 / 235 × 100 = 4.3%. A database that stores 235 MPa without a thickness condition will misrepresent the second case.

JR toughness and component selection

A 27 J Charpy classification is a test-based material requirement. It does not establish a universal minimum operating temperature, immunity from brittle fracture or an impact load rating for a complete component. Specify required verification and inspection documentation rather than assuming that the letters JR mean every delivered item has an individual impact-test result.

Select toughness using the governing design rules and actual thickness, stress state, restraint, weld details, service temperature and consequence of failure. Do not substitute JR for J0 or J2 merely because their room-temperature tensile properties look similar. Conversely, choosing a colder test class does not by itself complete the structural assessment.

Product declaration versus general grade

Thyssenkrupp's October 30, 2023 declaration concerns hot-rolled patterned strip S235JR/1.0038, identifies EN 10025-1:2004 as its designated standard, and declares properties through 25.4 mm nominal thickness. It gives 235 MPa minimum yield through 16 mm, 225 MPa above 16 mm within its stated range, 360–510 MPa tensile strength, and 27 J at 20°C. Keep this product and declaration context when reusing the numbers. Thyssenkrupp, patterned-strip declaration of performance

That declaration also gives a maximum carbon equivalent of 0.35% for its range. A CEV limit is useful welding information; it does not establish one universal preheat or permit arbitrary joint restraint, thickness and hydrogen conditions. Thyssenkrupp, weldability declaration

Keep the declaration’s product identifier and test scope with its values.

Delivery condition, fabrication and tolerances

Salzgitter Mannesmann Stahlhandel separately lists S235JR+N heavy plate and S235JR sheet cut from strip, with different dimensional offerings and EN 10204 type 3.1 documentation. This demonstrates why the delivery suffix and supply route should remain in the order. Availability listings are not proof that every possible dimensional combination is available. Salzgitter Mannesmann Stahlhandel, flat-products program

Record and confirm the meaning of the ordered delivery condition against the applicable standard and certificate. Review hot forming, straightening or subsequent thermal processing before assuming the certified properties remain applicable. Specify surface quality, cut edges, dimensional tolerances and flatness independently of the strength designation.

For welding, select the qualified procedure using actual product chemistry, thickness, joint geometry, restraint and service requirements. For cold forming, obtain the required formability assurance and qualify representative bends where necessary. Neither “structural steel” nor a CEV entry defines a universal bend radius or welding recipe.

Design and purchasing record

A practical record contains the exact grade and edition, product form, thickness, delivery condition, required inspection document and any additional testing. Attach project-specific toughness, through-thickness, surface or dimensional requirements explicitly. Retain heat traceability through cutting and fabrication where required.

Source dates and boundaries

DIN's listing identifies the October 2019 national adoption. Saarstahl's PDF is signed June 28, 2024, despite the download index showing July 18, 2024 and the URL containing an older upload path. Thyssenkrupp's declaration is dated October 30, 2023. No printed revision date was verified for the Tata slides or Salzgitter stock page. Confirm contract-required editions and current supply separately.

See also grades, tempers and conditions.