Visar resultat 1 - 5 av 11 avhandlingar innehållade ordet sigma-phase.
1. Influence of multiple welding cycles on microstructure and corrosion resistance of a super duplex stainless steel
Sammanfattning : Super duplex stainless steel (SDSS) has found a wide use in demanding applications such as offshore, chemical and petrochemical industries thanks to its excellent combination of mechanical properties and corrosion resistance. Welding of SDSS, however, is associated with the risk of precipitation of secondary phases and formation of excessive amounts of ferrite in the weld metal and heat affected zone. LÄS MER
Sammanfattning : Good toughness properties in base and weld material enable the use of duplex stainless steels (DSS) in critical applications. DSS offer high strength compared to common austenitic stainless steels. LÄS MER
Sammanfattning : A niobium stabilised AISI 347 austenitic stainless steel was investigated after static ageing and creep deformation at temperatures between 500°C and 800°C for times up to 88 000 h. Coarse and fine NbX precipitates and also s-phase precipitates were formed in the temperature range 500-700°C. LÄS MER
Sammanfattning : .... LÄS MER
Sammanfattning : Duplex stainless steels consist of about equal fractions offerrite and austenite and are attractive due to their highcorrosion resistance against pitting corrosion and stresscorrosion cracking. The pitting corrosion resistance can bedescribed by the PREN value which is defined asPREN=%Cr+3.3*%Mo+16*%N. LÄS MER