Research On Interface Microstructure And Properties Of 316L/Q370 Clad Plate By Explosive Welding

Stainless steel/carbon steel clad plate is widely used in the fields of aerospace,petrochemical,transportation,construction and other industries because of both the advantages of both stainless steel and carbon steel materials.Q370 is often used in highway bridges and railway bridges,but it can not meet the corrosion problem of steel bridge structure,it is the corrosion-resistance,expensive 316 L compound in the Q370 with high strength and low price and the formation of 316L/Q370 clad plate,with excellent comprehensive performance,is a single stainless steel and carbon steel can not match.In this paper,316L/Q370 clad plate was produced by explosive cladding,the mechanical properties and microstructure of clad plate were carried out,which can offer the theoretical guidance for the production of 316L/Q370 clad plate.Explosive welding parameters were chosen on the basis of the empirical formulas.A series of mechanical properties tests were performed,such as the tensile,shear,bending,impact and so on.Then the microstructure,element diffusion layer and fracture morphology of the clad plate were observed.Finally,the clad plate was annealed at different temperatures to eliminate the work hardening coming from the explosion impact and by comparing the change of properties and microstructure to determine the most suitable annealing temperature.According to the test results,the optimum explosive welding parameters for the 316L/Q370 clad plate are as follows: Wg =3.00 g·cm-2,h0 =8.00 mm.The mechanical properties test results show,the tensile strength of the clad plate is 617.19 MPa,the shear strength is 287.87 MPa,the impact absorbing energy at low temperature is 50.39 J;and has good bending performance,these properties have reached the national standard requirements;the fatigue strength of the clad plate is 305.52 MPa,which can be used as the basis for the selection of the bridge steel.The micro-hardness at the interface of the clad plate is the highest,and the micro-hardness decreases with the increase of the distance of the interface.Microstructure observation showed the microstructure of Q370 is F+P,the microstructure of 316 L is A,the interface is sonic wave;the thickness of the element diffusion layer is 1.50 ?m;the fracture morphologies of tensile,impact and fatigue are all plastic fracture.Annealing treatment results show,600? and 920 ?,with the temperature increase the yield strength,tensile strength decreases gradually,but the elongation increases with the increase of temperature;the microstructure of Q370 has become larger,but not significantly larger,316 L has no effect;the thickness of the diffusion layer becomes wider,but it does not affect its mechanical properties;after annealing,the micro-hardness decreased obviously,and the higher the annealing temperature was,the more the micro-hardness decreased.These comparison indicates that 600? for proper annealing temperature.