Abstract

VILLALOBOS-VERA, Doris Ivette  and  MENDOZA-BRAVO, Ivan. Microstructural Transformation in the Root Pass of Superduplex Stainless Steel Multipass Welding. Ing. invest. y tecnol. [online]. 2017, vol.18, n.2, pp.193-198. ISSN 2594-0732.

This work focuses on the identification of secondary phases in a superduplex stainless steel multipass welding performed by means of the GMAW process using two filler metals, one of the duplex type and the other of the superduplex type. To identify the secondary phases in the welding metal and the heat affected zone, the samples were analyzed by optical microscopy. The results showed a considerable formation of sigma phase in the welding metal in both samples, making evident the total consumption of ferrite. On the other hand, the heat affected zone corresponding to the superduplex-type filler metal, presents a remarkable sensitization, probably due to the occurrence of chromium nitrides in the center of the ferrite grains while the heat affected zone corresponding to the duplex-type filler metal depicts a more balanced microstructure of ferrite, austenite and secondary austenite.

Keywords : thermal cycle; superduplex stainless steel; sigma phase; welding; GMAW; heat affected zone; welding metal.

        · abstract in Spanish     · text in English     · English ( pdf )