Soudage des aciers inoxydables destinés aux milieux corrosifs sévères

Welding of stainless steels for highly corrosive media

Creusot-Loire Industrie, Division Creusot- Marrel, Le Creusot

Abstract

Two families of high chromium and/or molybdenum stainless steels have been developed in recent years for highly corrosive process conditions : duplex steels with a ferritic + austenitic microstructure ; super austenitic steels with a high alloyed fully austenitic structure. Proper fabrication and welding techniques must take into account the metallurgical effects of welding (due to the thermal and mechanical cycles) for each family of alloys. Cracking risk, microstructural and mechanical properties and corrosion resistance of welded joints have been studied. The use of proper welding conditions and filler materials leads to a behaviour of welds as well as that of base material.