Steel grades

General-purpose engineering structural steel — ReH >=295 MPa. Formerly St 50-2 (DIN 17100). Higher strength than S235 but not intended for welded structures (higher C, no guaranteed weldability). Used for machine bases, frames, pins, keys, and general engineering parts where moderate strength without welding is sufficient. Not suitable for cold forming.

Highest-strength unalloyed structural steel in EN 10025-2 — former designation St60-2 (DIN 17100). Higher C and Mn than S355 giving UTS 570-710 MPa. Not intended for welding (high CEV). Used for shafts, axles, bolts, and machine parts where weldability is not required but higher strength than S355 is needed. "E" designates engineering steel (vs "S" for structural).

Highest-strength unalloyed structural steel in EN 10025-2 — ReH ≥360 MPa minimum. Not intended for welding (high C ~0.57%). Used for general engineering where maximum unalloyed strength is needed without heat treatment: machine beds, crane components, wear plates, and structural members not requiring welding. Formerly St 70-2 (DIN 17100).

Cr-Mo-V hot-work tool steel — close relative of H13 with slightly lower C and V. Good hot hardness, thermal fatigue resistance and toughness. Used for forging dies, extrusion tooling, mandrels, and die-casting tools. Often preferred over H13 where higher toughness is needed.

The most widely used hot-work tool steel globally. Excellent combination of hot hardness, toughness, and thermal fatigue resistance. Used for die-casting dies (aluminum, zinc, magnesium), forging dies, extrusion tooling, and hot shear blades.

Standard cobalt high speed steel with 5% Co — the most widely used cobalt HSS grade. Also known as M35 or HSS-E/HSSE. Better hot hardness and cutting performance than M2, lower cost than M42. HRC 64-66 hardened. The "go-to upgrade" when M2 performance is insufficient. Used for drill bits (HSS-Co branded), taps, end mills, saw blades, and general-purpose cutting tools for stainless steel and medium-hard alloys.

Lean duplex stainless steel with minimal Ni and Mo — the most cost-effective duplex grade. Uses Mn and N instead of expensive Ni for austenite stability. Double the yield strength of 304 (450 MPa vs 190 MPa). Used as a direct replacement for 304/316L where higher strength or better SCC resistance is needed.

Lean duplex stainless steel with low Mo content. More economical than 2205 with better corrosion resistance than 304/316L. Developed for construction, water treatment, and storage tanks where full duplex properties are not required.

The most widely used high-speed steel worldwide. W-Mo-Cr-V composition gives excellent red hardness (cuts at temperatures up to 600°C). Used for twist drills, end mills, taps, reamers, bandsaw blades, and general-purpose cutting tools. The benchmark HSS grade.

Cobalt super high speed steel — 8% Co for maximum hot hardness (HRC 69 at 550°C). THE HSS for machining superalloys, titanium, and pre-hardened steels where M2 burns out. Mo-series (not W-series like T15). Reaches HRC 68-70 after hardening — among the hardest HSS grades. Also known as HS2-9-1-8 (EN) or SKH59 (JIS). Used for drills, end mills, taps, broaches, and milling cutters for difficult-to-machine materials.

Oil-hardening cold-work tool steel. Good balance of wear resistance, toughness, and machinability at moderate cost. Very predictable heat treatment response. The standard choice for hand tools, gauges, jigs, fixtures, taps, reamers, and general precision tooling.

Pre-hardened plastic mold steel (usually delivered at 28-34 HRC). The most widely used mold base steel globally. Good machinability in pre-hardened condition, good polishability. Used for injection molds, die-casting dies, extrusion tooling, and structural mold components.

Lowest-strength pressure vessel steel — ReH >=235 MPa. Excellent weldability due to very low C (max 0.16%). THE entry-level boiler/pressure vessel plate in EN 10028-2. Used for low-pressure vessels, boiler drums, heat exchangers, and steam piping at modest pressures and temperatures to ~400°C.

Unalloyed pressure vessel steel — THE standard boiler plate material in Europe. ReH >=265 MPa, good weldability, guaranteed elevated-temperature properties to ~450°C. "GH" = suitable for use at elevated temperatures. Used for boilers, pressure vessels, heat exchangers, and steam drums per EN 10028-2 and PED 2014/68/EU.

Mid-range pressure vessel steel — ReH >=295 MPa. Between P265GH and P355GH. Used for unfired pressure vessels, heat exchangers, and boiler components per EN 10028-2. Good weldability and guaranteed elevated-temperature yield strength. Widely specified in European process plant design.

Higher-strength pressure vessel steel — ReH >=355 MPa, guaranteed elevated-temperature properties. Between P265GH and 16Mo3 in the pressure vessel hierarchy. Used for boilers, steam drums, heat exchangers, and pressure piping operating to ~400°C. EN 10028-2, PED 2014/68/EU compliant. Good weldability.

Normalized pressure vessel steel with low-temperature toughness — ReH >=355 MPa, Charpy at -40°C (KV >=27J). "NL" = Normalized + Low-temperature. Used for pressure vessels, storage tanks, and process equipment operating in cold environments (LPG, cryogenic). EN 10028-3 + PED compliant.

Highest-strength normalized pressure vessel fine-grain steel — ReH >=460 MPa. "N" = normalized, "H" = elevated temperature. Used for high-pressure vessels, boiler drums, and chemical reactors where maximum strength with guaranteed elevated-temperature properties is needed. EN 10028-3 + PED compliant. Good weldability due to fine grain and controlled CEV.

Premium aerospace precipitation-hardening stainless. Al-precipitation for the highest transverse toughness and most uniform properties of all PH stainless grades. SCC-resistant in marine environments. Used for landing gear, structural airframe parts, nuclear components, and high-performance shafts.

The cheapest and lowest-grade structural steel in EN 10025-1. Only tensile strength is guaranteed (290-510 MPa), no guaranteed yield strength, composition, or impact toughness. Used for non-critical structural applications, fences, lightweight frameworks, and temporary structures where only minimum strength is needed.

Basic structural steel with guaranteed Charpy impact at 0°C (KV >=27J). Better low-temperature toughness than S235JR (which only guarantees 27J at +20°C). Same strength class (ReH >=235 MPa). Used for general structural applications in moderate climates: building frames, bridges, storage tanks, and platforms. Very widely available and cost-effective.

Basic structural steel with guaranteed -20°C impact toughness. The toughest variant in the S235 family (J2 = 27J at -20°C). Used for welded structures in moderately cold environments, general structural fabrication, and applications where S235JR's 20°C impact is insufficient.

General-purpose structural steel with minimum yield strength of 235 MPa. The most common structural steel grade in Europe for general construction, frames, and non-critical structural applications.

Structural steel with guaranteed Charpy impact at 0°C (KV >=27J). Between S235J0 and S355J0 in the strength range. ReH >=275 MPa. Very widely used in European construction: building frames, columns, beams, and general structural applications. Good weldability. Often specified as standard section material (IPE, HEA, UPN profiles).