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.

Characteristics of Greek Ascoloy (Alloy 418)

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

We stock Greek Ascoloy (Alloy 418) in a variety of product forms to suit different applications and fabrication methods, including round bar and sheet. To view available sizes and submit an inquiry, use the dropdown selector below.

Round Bar
Sheet

Chemical analysis

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

Key Properties

  • Density: 7.86 g/cm³

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.

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)

Applications of Greek Ascoloy (Alloy 418)

  • Compressor components
  • Steam and gas turbine blades
  • Steam turbine buckets
  • Elevated temperature bolts
Proud members of the British Valve & Actuator AssociationProud members of the British Valve & Actuator Association