Influence of pass reduction ratio on microstructure and properties of 2205/Q235B clad steel plate

2205/Q235B clad steel plates were fabricated using a thermal simulator.The metallographic microscope,scanning electron microscope,energy-dispersive spectrometer,shear test,electrochemical corrosion test and acid immersion test were used to study the influence of the pass reduction ratio on the microstructure and properties of 2205/Q235B clad steel plate.The results show that the clad steel plates had a good bonding surface when the pass reduction ratios were between 16.3%and 36.0%.There existed the mutual diffusion effect of elements near the bonding surface,which caused the long austenite strip on the side of 2205 stainless steel and the decarburization layer on the side of Q235B low-carbon steel.The transformation ofδferrite toγaustenite and the generation of the decarburization layer were promoted because of the lower pass reduction ratio.The corrosio n resista nee of 2205 duplex-phases stainless steel worse ned by the decrease in 8 ferrite con tent.The increase in the decarburization layer thickness made the shear strength of the clad steel plates reduce from 453 to 390 MPa.The potential of the decarburization layer was lower than that of 2205 stainless steel and Q235B low-carb on steel,which was easily corroded in the corrosive medium.

Effect of Heat Treatment on the Microstructure,Mechanical Properties and Corrosion Resistance of Selective Laser Melted 304L Stainless Steel

The influence of heat treatment holding temperatures from 600 to 1300℃ on the microstructure,mechanical properties and corrosion resistance in selective laser melted(SLMed)304L stainless steel is investigated in this work.The results reveal that there is no remarkable microstructure change after holding at 600℃ for 2 h,while recrystallization leads to a slight decrease in grain size in the temperature range of 700–900℃.The heat treatment at temperatures from 1000 to 1300℃ for 2 h obviously affects the morphology of grains in SLMed 304L stainless steel.Combining effects of grain coarsening,delta-ferrite(δ)phases reduction and residual stress release during heat treatment lead to the reduction of yield strength and an increasing elongation.The elongation of the samples heat treated at 800℃ for 2 h is,however,significantly decreased due to the increase in the amount of sigma(σ)phase.A remarkable increase in the amount ofδferrite results in an increase in yield strength but a decrease in ductility after heat treatment at 1300℃ for 2 h.The corrosion resistance of the samples heat treated at 1300℃ is significantly improved due to the substantial reduction of brittle phase(σ).There is no obvious effect of the presence ofδferrite on corrosion behavior.