Delta-ferrite development in weld and HAZ produced by pulsed plasma arc welding in a supermartensitic stainless steel [Desenvolvimento da ferrita delta na solda e ZTA resultante de soldagem plasma pulsada em urn aço inoxidável supermartensítico]
Henke S.L.,Federal University of Paraná |
Paredes R.S.C.,Federal University of Paraná |
Capra A.R.,Institute Of Tecnologia Para O Desenvolvimento Lactec
Soldagem e Inspecao | Year: 2013
The objective of this study was to investigate the effect of pulsed plasma welding on the distribution and amount of delta ferrite which is considered an undesirable phase in a supermartensitic stainless steel. For such weld beads have been obtained by melting the surface of a sample of a high-alloy supermartensitic stainless steel using pulsed and conventional current. Microstructural characterization, especially of delta ferrite, was performed by metallographic analysis by means of optical microscopy and scanning electron microscopy. The experiments showed that for the same heat input, pulsed current promoted the formation of delta ferrite in the form of bands along the weld bead and caused a significant reduction of this phase in HAZ as compared to conventional welding.