Microstructure of the bonding interface in an explosively cladded 2205 duplex stainless steel-16MnR steel combination

The experimental sample with the dimensions of 25 mm×50 mm was formed with a 4-mm-thickness 2205 duplex stainless steel(DSS) plate as the flyer base and a 20-mm-thichness 16MnR steel plate as the base plate by explosive combination.The flyer plate and base plate were treated with different methods,respectively.The bonding interface morphology was observed with a Nikon Epiphot 200 inverted microscope and a Hitachi S-3000N scanning electron microscope(SEM).The whole bonding interface is made of straight and vortical bond zones and can be divided into melt and plastic deformation zones.And Energy dispersive spectroscopy analysis displays that the bonding interface takes on a satisfactory metallurgical bond.The experimental samples were annealed in an electric resistance furnace SX-4-10 and the microhardness was measured by an HV-1000 cleraometer.After the sample was heat-treated at 850 ℃ for 8 h and cooled until 400 ℃,and cooled in air,in the 2205 DSS plate there was σ-phase precipitated in the austenite-ferrite interspace or in ferrite.And after the sample was heat-treated at 700 ℃ for 8 h and cooled until 400 ℃,and cooled in air,there was not σ-phase observed in the bonding interface.Analysis of heat treatment influences on the microhardness indicates that the microhardness of the base and flyer plates decreases with the increasing of temperature and time of heat treatment.