| For duplex stainless steels (DSS) welded components the microstructural balance (50% ferrite - 50% austenite) that gives their good mechanical properties and corrosion resistance can be lost at the joint. Transient liquid phase (TLP) bonding is a joining process that can produce homogeneous microstructure at the bond region. The present work studied the effect of bonding time and grain orientation (i.e. rolling and transverse directions) on the metallurgical properties of TLP bonds of DSS using Cu interlayers. Good microstructural continuity without detrimental brittle phases (i.e. sigma and chi) and acceptable austenite volume fraction was obtained. However, presence of voids associated with wettability problems, austenite grain growth and lower hardness than the base metal were observed. In general, the chemical composition at the bonding interface was close to that of the base metal, and lower Cu concentration at the joint was observed when the surfaces where transverse to the rolling direction. |
