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DKL Engineering, Inc.
Materials of Construction - LEWMET®
July 2, 2003
LEWMET® designates a series of austenitic nickel-chrome alloys designed specifically as construction materials for use in sulphuric acid plant service. Since 1970, LEWMET® has been regularly and successfully employed in critical wear parts to resist corrosion/erosion/galling in areas having fluid velocities of more than 30.5 m/s (100 ft/s). Extensive corrosion testing indicates a corrosion rate of approximately 0.0762 mm/year (0.003 inches/year) in 98% H2SO4 at 120°C.
LEWMET® owes its superior performance to a unique combination of alloy composition and hardenability. LEWMET® is a nickel-based alloy containing approximately 30% nickel, 30% chromium as well as molybdenum, silicon, copper, manganese and boron. LEWMET® can be hardened to 500 Brinnel without compromising its excellent corrosion resistance.
Due to the proprietary nature of the material there is not much published information concerning LEWMET® materials. Contact Chas. S. Lewis for further information.
|LEWMET® 15||LEWMET® 33||LEWMET® 55||LEWMET® 66|
|Description||High chromium duplex stainless steel||Two-phase casting alloy||Fully austenitic nickel-base alloy|
|Introduced||Early 1970’s||Late 1970’s|
Cast and wrought
Plate and Wire
|Application||98%, 135oC max.|
Lewmet® 55 Isocorrosion Curve
Lewmet® 66 Isocorrosion Curve