Defining Acceptable Environmental Ranges and Welding Procedures for Corrosion Resistant Alloys

Defining Acceptable Environmental Ranges and

Defining Acceptable Environmental Ranges and Welding Procedures for Corrosion Resistant Alloys
by
J R Crum and L E Shoemaker
Special Metals Corporation
ABSTRACT  
The term “corrosion resistant alloys” (CRA’s) covers a wide range of materials from ferritic stainless steels to nickel base or titanium alloys.  Nickel, chromium and molybdenum contents increase steadily as we progress from ferritic, duplex, super-duplex, austenitic, 6% or 7% molybdenum super-austenitic stainless steels to nickel-chromium-molybdenum-tungsten alloys.   As this progression is made the corrosion resistance, and cost, increase dramatically.  A definitive ranking of the general and localized corrosion resistance of these materials in a variety of environments is provided, with special emphasis on effects of welding and choice of filler metals.