Study On The Preparation Of Stainless Steel/45 Steel Clad Plates And Its Interfacial Phenomena

As a substitute for pure stainless steel,clad plates composed of stainless steel and 45 steel have become popular for saving precious metals,lowering the cost and achieving a higher performance.In this paper,the 304 stainless steel/45 steel clad plates and 304 stainless steel/Ni/45 steel clad plates were fabricated by hot-rolling in an argon atmosphere.The interfacial microstructures of the clad plates were observed by SEM,and the interfacial diffusion of alloying elements were determined by EDS.The interfacial hardness was tested by hardness testing device,and the shear strength was tested by a home-made set-up with reference to the related criteria.The effect of the rolling parameters on microstructure and mechanical properties and composition diffusion was analyzed.The results show that both the dimension and number of interfacial pores of clad plates decrease rapidly with increasing rolling passes and rolling temperature.The shear strength values increase with increasing bonding temperature;However,the values increase at first and then decrease with the rolling pass number.The shear strength decreases with increasing rolling passes at 1150 and the shear strength increase at first ?and then decrease with the rolling pass number at 1050? and 950.What's more,the ?maximum shear strength at the second pass.The maximum shear strength reaches 469 MPa at 1050 ?with accumulative deformation rate of 19.12% and the minimum shear strength reaches 380 MPa at 950 with accumulative deformation rate of 63.543%.?When the Ni foil is added between the stainless steel and the 45 steel,the shear strength values increase with increasing both bonding temperature andaccumulative deformation rate.What's more,the maximum shear strength reaches 414 MPa at 1150 ?with accumulative deformation rate of 63.383% and the minimum shear strength reaches 343 MPa at 950 with accumulative deformation rate of 19.711%.?The stainless steel is roll bonded together with the 45 steel by hot rolling in this paper.The carbon will diffuse from 45 steel to stainless steel when thetwo plates are roll bonded.Carbon atoms pass through the bonding interface tothe stainless steel side and are combined with chromium atoms to form chrom-ium carbides which concentrate on the interface,so that the decarurization region is present on the 45 steel side because of the diffusion of carbon element and the sensitization region is present on the stainless side because of the depletionof chromium.The decarburization region consists of the full-decar-burization zone and semi-decarburization zone.The sensitization region is com-posed of adual structure,ditch and full-depletion of chromium zones.With theincreasing of rolling temperature and cumulative deformation rate,the diffusionof interfaceis more serious and the width of decarburization region and sensitization regionwill increase.After five rolling passes,the width of decarburization region is approximately 82 ?m and the width of depletion of chromium zone is 55 ?m.The shear strength will increase because of the concentrating of chromiumcarb-ides.The results show that the Ni foil can effectively restrain even prevent the diffusion of carbon,so that it can improve the corrosion of the composite interface.However,with the increasing of thickness of the Ni foil,the interfacial shear strength will decrease,so the thickness of Ni foil should be controlled properly.