Steel

Nickel-chromium-molybdenum-vanadium hot work tool steel with outstanding toughness. 1.7% Ni provides superior shock resistance and toughness at working temperatures. Hardened to 44–50 HRC. Used where maximum impact resistance is needed: hammer dies, forging dies, drop forge inserts, hot shear blades, plastic mold base plates and large press tools. The standard material for heavy forging dies in the automotive and aerospace forging industry.

Silicon spring steel — Si (1.5-2.0%) provides high elastic limit and excellent fatigue resistance without expensive Cr/V additions. Better heat resistance than Cr-spring steels — retains spring properties to ~250°C. Used for valve springs, clutch springs, hot-wound coil springs, and applications with moderate elevated temperature exposure. Cheaper than CrV spring steels.

Heavy-duty hot work tool steel with high Ni (1.5-1.8%) for exceptional toughness at working hardness. THE forging die material for hammers and presses. Better impact resistance than H13 but lower hot hardness. Also used as backing steel for composite dies. Applications: forging dies, die holders, press tools, shear blades, and heavy-duty punches.

High-carbon chromium-vanadium spring steel — higher C (0.55-0.62%) than 51CrV4 (0.47-0.55%) for maximum hardness and fatigue strength. V refines grain and improves temper resistance. Used for the most demanding spring applications: heavy-duty coil springs, torsion bars, stabilizer bars, and spring tools. Also used as tool steel (1.2242/59CrV4 variant).

Silicon-chromium valve spring steel — the highest fatigue life among EN 10089 spring steels. High Si (1.50-1.80%) provides excellent resistance to relaxation at elevated temperatures (up to ~250°C). Superior to 51CrV4 for high-stress, high-cycle applications. Used for automotive valve springs, heavy-duty coil springs, torsion bars, and stabilizers. ≈ AISI 9260.

Shock-resisting cold work tool steel (AISI S1) with tungsten and high silicon for exceptional toughness and impact resistance. Oil hardening. Achieves 52-60 HRC. Very good dimensional stability during heat treatment. Used for blanking and stamping dies for sheet up to 12mm, cold piercing punches, shear blades, pneumatic chisels, coining tools, woodworking tools, and ejectors. The premium choice where impact resistance is more critical than maximum wear resistance. Also known as 60WCrV7 (older DIN designation).

Precipitation-hardening martensitic stainless steel — the highest-strength stainless in common use. Solution anneal at 1040°C then age at 480-620°C for UTS >1300 MPa. Corrosion resistance similar to 304. Cu+Nb precipitation hardening. Trade names include 17-4PH, SUS630. Used for aerospace structural parts, turbine blades, valve components, nuclear waste casks, medical instruments, and oil/gas equipment.

Nickel-chromium-molybdenum case-hardening steel. Good combination of core toughness and case hardness. The most widely used case-hardening steel in the US (AISI 8620). Used for gears, pinions, worm drives, king pins, and cross-shafts.

Super-austenitic stainless steel with high Mo and Cu content. Excellent resistance to sulfuric acid, phosphoric acid, and chloride environments. Bridges the gap between standard austenitics (316L) and nickel alloys (Inconel/Hastelloy). Used in chemical processing, oil & gas, and pharmaceutical.

Universal cold work tool steel with high carbon and manganese. Oil hardening (AISI O2). Excellent dimensional stability during heat treatment, good wear resistance, and high hardness up to 63 HRC. Easy to machine in annealed condition. Used for blanking and stamping tools, precision punches, shear blades, thread chasers, reamers, measuring gauges, woodworking tools, and cold forming dies. Equivalent to AISI O2.

Free-cutting steel with high sulfur for excellent machinability. Very similar to 11SMn30 — historical German designation that is still widely referenced. Lower C variant preferred for some screw machine products. Used for high-volume automatic lathe parts, screws, nuts, pins, and bushings. ≈ AISI 1215.

Leaded free-cutting steel — Pb (0.15-0.35%) + S (0.24-0.33%) for maximum machinability. THE ultimate Automatenstahl: machinability rating ~175% (vs 100% for 11SMn30). Pb acts as chip-breaker and tool lubricant. Used for high-speed automatic screw machine production of screws, nuts, fittings, bushings, and any part where surface finish and cycle time matter most. NOTE: Pb content being phased out under EU ELV/RoHS — replacement grades emerging.

Air-hardening cold-work tool steel. Combines good wear resistance with excellent dimensional stability during heat treatment (minimal distortion). Used for punching/blanking dies, forming tools, shear blades, gauges, and precision tooling where low distortion is critical.

Cr-Mo quench-and-temper alloy steel — the lower-carbon version of 4140 (42CrMo4). Lower C (0.33-0.38%) gives better weldability and toughness than 4140 with slightly lower strength. Primarily a US/ASTM designation. Used for drill pipe, tubing, couplings, and oil field applications where weldability matters more than maximum strength.

Powder metallurgy high speed steel by Erasteel (now Zapp). Co-free PM-HSS with excellent combination of wear resistance and toughness. C 1.28%, Cr 4.2%, Mo 5.0%, W 6.4%, V 3.1%. Hardness 64–67 HRC. Superior carbide distribution vs conventional HSS. Applications: end mills, drills, taps, broaches, cold forging punches, fine blanking tools. Alternative to M42 and S390.

The most common structural carbon steel in the US. Low carbon content with good weldability and machinability. Used for buildings, bridges, construction equipment, and general structural purposes. Minimum yield strength 36 ksi (250 MPa).

The most widely used structural steel grade in the United States. 345 MPa (50 ksi) yield strength HSLA steel. Has largely replaced A36 for structural applications due to higher strength-to-weight ratio. Used for building frames, bridges, heavy equipment, and general structural fabrication.

High-strength low-alloy weathering steel. Forms a stable protective rust patina eliminating the need for paint. Cu-Cr-Ni-V composition provides 4-8x atmospheric corrosion resistance vs carbon steel. Used for unpainted bridges, architectural facades, sculptures, outdoor structures, and freight cars.

Low-carbon unalloyed steel. Excellent weldability, good formability, and low hardness. Used for pins, rivets, bushings, case-hardened parts with thin case depth, and general cold-formed components. Can be case-hardened for surface wear resistance.

Highest-carbon unalloyed spring/tool steel — C 0.95-1.05%. Maximum hardness (HRC 63-66) in the unalloyed range. On the boundary between spring steel and tool steel. Used for flat springs requiring absolute maximum hardness, doctor blades, cutting tools, cold stamping dies, and wood-working saw blades. Also known as Silberstahl (silver steel) in wire form.

Lowest practical carbon case-hardening steel — 0.07-0.13% C. After carburizing: hard surface (HRC 55-60) with extremely soft, tough core (HRC 15-20). Maximum impact absorption. Modern designation for Ck10. Used for pins, bushings, small gears, camshaft lobes, and any carburized part where maximum core toughness and ductility are critical. Also used as cold-heading and deep-drawing wire/strip.

Low-carbon unalloyed case-hardening steel. The simplest and most economical case-hardening grade. Used for lightly loaded gears, pins, bushings, rivets, and small machine parts where a hard wear-resistant surface with a soft tough core is needed.

Low-carbon unalloyed case hardening steel — 0.12-0.18% C. Between C10E (softer core) and C22E (harder core) in the case-hardening range. Good balance of surface hardness (HRC 58-62) and core toughness after carburizing. Modern designation for Ck15. Used for small gears, pins, bushings, levers, and carburized parts where moderate core strength is acceptable. Also used for cold forming and deep drawing.

Low-carbon unalloyed steel for case hardening (carburizing). 0.17-0.23% C gives a tough core with a hard, wear-resistant surface after carburizing + quenching. The simplest and cheapest case-hardening steel. Used for pins, bushings, cam followers, light-duty gears, and general machine parts where a hard surface with tough core is needed. ≈ AISI 1020.