TIG welding of Uranus 45N duplex stainless steel: Changes in microstructure and properties

Summary

The purpose of this paper is to study the development of mechanical properties and microstructure in three TIG welded joints, as a function of the distance to the weld centreline and the welding conditions. Three different heat inputs have been analysed for Uranus 45N duplex stainless steel for the purpose of studying microstructures in weld metals and HAZs, such as the development of hardness and ferrite content with distance from the weld centre. Ferrite content was determined by X-ray diffraction and methods based on magnetic properties of ferrite. In addition, a brief bibliographic review was carried out on solidification microstructure and high temperature transformations occurring in this type of steel. Finally, thermal cycles and distribution studies of welds using mathematical models proposed by other authors have been examined, to determine their suitability for Uranus 45N.