ATI 418 SPL™ alloy (Greek Ascoloy) is a corrosion and heat resistant stainless steel smilar in many respects to Type 410 but exhibiting improved high temperature properties. ATI 418 SPL alloy is a modification of former AISI Type 418; the only difference is that nickel has been added to prevent the formation of delta ferrite. Up to 1100°F, its stress rupture strength is equal or superior to the austenitic stainless steels. It can be hardened to Rc 45 typical when quenched from 1750°F or Rc 50 typical when quenched from 1850°F.

ATI 418 SPL alloy is readily forgeable and has fair machinability and cold formability in the annealed condition.

ATI 418 SPL alloy can be welded by any of the commonly used processes; but since it is air hardening, welded sections should be annealed or tempered for maximum ductility.

ATI 418 SPL alloy is commercially available as sheet, strip and plate and is produced to the AMS 5508 specification.

APPLICATIONS
ATI 418 SPL alloy is used for stream and gas turbine parts, jet engines and high pressure steam valves. It is suggested for service in the 750-1100°F range where good strength and oxidation resistance are desired.