Complaint
In addition to providing the widest range of materials to many different sectors, we are the only company who can melt and forge according to customer requests and produce in the form closest to the final product. We provide services that will increase the added value in products by adding our mechanical processing and heat treatment capabilities to our forging products, which are produced in requested forms from automotive to energy, from maritime to mold industry.
A martensitic chromium-tungsten-nickel stainless grade, Greek Ascoloy (Alloy 418) is ideal for high-stress components up to 649ºC
Stainless Steel 418, also known as 'Greek Ascoloy (UNS S41800) is engineered for use in high-stress components.
| Grade | UNS | Carbon | Manganese | Phosphorus | Sulfur | Silicon | Chromium | Nickel | Molybdenum | Tungsten |
| 615 | S41800 | 0.15-0.20 | 0.50max | 0.04 | 0.03 | 0.50max | 12.00-14.00 | 1.80-2.20 | 0.50max | 2.50-3.50 |
| MECHANICAL& PHYSICAL PROPERTIES | 21ºC |
| Ultimate Tensile Strength/MPa | 965 |
| 0.2% Yield Strength /Mpa | 760 |
| Elongation % | 15 |
| Hardness(Brinell) | 302-352(311 max. for annealed material) |
Greek Ascoloy 418 stainless bar is a higher strength modification of the 12% chromium family of martensitic stainless steels. It's a precipitation, age hardenable stainless steel that features transverse toughness. It can be machined in all conditions. Greek Ascoloy retains corrosion and oxidation resistance and has usable strength and creep resistance to 1050ºF (566ºC). This grade is used for jet engine compressor blades and vanes due to resistance to stress corrosion cracking. Also used for discs in lower temperature turbine stages and for turbine diffuser components.
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 ºC. Typical heat treatment at 980°C -1010ºC followed by air or oil quenching (depending on material thickness) and 2-hour tempering twice at minimum 620ºC gives Greek Ascoloy (Aloy 418) a superior creep strength and resistance to stress corrosion cracking and tempering as compared to the general properties of 12% chromium stainless steels. Filer metal, UNS S41880, has extra molybdenum (0.50 max.), copper (0.50max) and tin (0.05 max) for effective welding process.
The corrosion resistance of Greek Ascoloy 418 stainless bar is similar to Alloy 410 stainless bar. This grade resists oxidation up to 1400ºF (760ºC) and may be used in continuous service at 1100ºF (593ºC). A wide range of mechanical properties can be obtained by hardening and tempering this alloy.
Hardness of stock is typically 250 BHN. Supplied in the fully annealed condition. Hardening of this grade is accomplished by austenitizing at 1750-1800ºF (954-982ºC) followed by air or oil quench to form martensite.Immediately following austenitizing, tempering should be carried out in the range of 1000-1250ºF (538-677ºC) for two hours. The hot working range is 1700-2150ºF (927-1177ºC). Large sections should be preheated at 1200-1400ºF (649-760ºC) to prevent strain cracking.
Machinability
Rating: 55% OF B-1112.
Typical stock removal rate: 90 surface feet/minute with high speed tools, 150 surface feet/minute with carbide.
Best machinability is in the fully annealed condition. Greek Ascoloy 418 stainless bar has a low work hardening rate and is not "gummy" like austenitic stainless steels during machining.
