NeoNickel

Greek Ascoloy (Alloy 418)

A martensitic chromium-tungsten-nickel stainless grade, Greek Ascoloy (Alloy 418) is ideal for high-stress components up to 649⁰C.

Stainless Steel 418, also known as ‘Greek Ascoloy’ (UNS S41800) is engineered for use in high-stress components.

  • UNS Number: S41800
  • AMS: 5616, 5508

Product availability

Round Bar
Sheet

Chemical analysis

%CCrWNiPSSiMnFe
Min0.1512.002.501.80----Balance
Max0.2014.003.502.200.040.030.500.50-

Applications

  • Compressor components
  • Steam and gas turbine blades
  • Steam turbine buckets
  • Elevated temperature bolts

About Greek Ascoloy (Alloy 418)

Stainless Steel 418, also known as ‘Greek Ascoloy’ (UNS 41800) is a heat resisting martensitic chromium-tungsten-nickel stainless steel. Greek Ascoloy is engineered for use in high-stress components up to 649 ⁰C.

Typical heat treatment at 980⁰C -1010⁰C, followed by air or oil quenching (depending on material thickness) and 2-hour tempering twice at minimum 620⁰C gives Greek Ascoloy (Alloy 418) a superior creep strength and resistance to stress-corrosion cracking and tempering as compared to the general properties of 12% chromium stainless steels.

Filler metal, UNS S41880, has extra molybdenum (0.50 max.), copper (0.50 max.) and tin (0.05 max.) for effective welding process.

  • Density: 7.86 g/cm³

Mechanical & Physical Properties

Mechanical & Physical Properties21⁰C
Ultimate Tensile Strength /MPa965
0.2% Yield Strength /Mpa760
Elongation %15
Hardness (Brinell)302-352 (311 max. for annealed material)
Proud members of the British Valve & Actuator AssociationProud members of the British Valve & Actuator Association