Corrugated Rolling Process And Properties Of Ti/Cu/Ti Composite Plate

Titanium has good corrosion resistance and is often used as the matrix material of electrochemical anode,but the resistivity of titanium is high.So it is difficult to meet the requirements of electrical conductivity of electrode materials.To solve this problem,this paper combines the excellent electrical conductivity of copper with the corrosion resistance of titanium and uses a new double corrugated roll rolling method to prepare Ti/Cu/Ti composite plate.This "sandwich" double corrugated composite plate can not only meet the requirements of electrical conductivity and corrosion resistance of electrode materials in a corrosive environment but also has good mechanical properties.In this paper,the effects of double corrugated roll rolling and traditional double flat roll rolling on the mechanical and electrochemical properties of Ti/Cu/Ti composite plate were studied,and the plastic deformation behavior of Ti/Cu/Ti composite plate during the two rolling processes was simulated by ABAQUS software.The mechanical properties,electrical conductivity,and corrosion resistance of Ti/Cu/Ti composite plate were tested by a universal tensile testing machine and electrochemical workstation.The morphology of peeling fracture,tensile fracture and interface microstructure,and the elemental distribution,and phase of the Ti/Cu/Ti composite plate were analyzed using SEM,EDS,XRD,EBSD,and so on.The finite element simulation results show that under the same reduction rate,the rolling force of double corrugated rolling is 13% larger than that of ordinary double flat rolling,and the equivalent strain,equivalent stress,and shear force are also larger.Due to the effective increase of the bonding interface of the corrugated composite plate and the increase of the rolling force,it also aggravates the extension of the plate to the width direction and promotes the shear deformation,which is beneficial to the tearing of titanium and the breaking of the hard and brittle layer,so that the softer copper metal is squeezed in to promote the tearing bonding of the interface.Besides,the large heat generated in the process of plastic deformation also significantly improves the bonding properties.The experimental results show that the comprehensive performance of Ti/Cu/Ti corrugated composite plate is the best.When the reduction rate is 50%,the highest bonding strength of the corrugated composite plate is 20.44N/mm.At this time,its tensile strength is 370.93 MPa,which is 52.8% higher than the theoretical value 242.75 MPa,and the elongation is 19%.The good combination of the interface of the corrugated composite plate is attributed to the joint action of many mechanisms: the corrugated interface effectively increases the interface contact area,and the strong stress and friction shear deformation promote metal flow and the breaking of the hard and brittle layer to expose more fresh metals.Also,when the double corrugated rolling method is adopted,the work hardening of the composite plate is weak,the degree of deformation is large,the interface is good,the grain is refined,and the composite plate has good tensile properties.Through the electrochemical tests,it is found that the corrugated composite plate with reduction 50% shows the best corrosion resistance and excellent electrical conductivity.The dislocation density of the composite plate obtained by double corrugated roll rolling becomes smaller,no impurities,no precipitated phase,and grain refinement,which not only increases the number of active atoms in the titanium layer and promotes the ability to form a passivation film on titanium surface,but also promotes the twinning and recrystallization of the copper layer as a result,a large number of dislocations are consumed and the dislocation density of the copper layer is reduced so that the composite plate has both excellent electrical conductivity and corrosion resistance.