Interfacial Diffusion Behavior And Molecular Dynamics Simulation Of Titanium/Steel Clad Plate During Heating Process

Ti/steel composite plate is an important composite material,which combines the excellent corrosion resistance of titanium and the high strength and low cost of steel.It is widely used in aviation,automobile,ship and other fields.The performance of Ti/steel composite plate is closely related to the interface diffusion behavior and bonding performance.The heating process has an important influence on the final product quality of Ti/steel composite plate.In view of the problems of insufficient element diffusion or excessive brittle interface formation in the heating process of Ti/steel composite plate,this paper studies the diffusion behavior and diffusion mechanism of the interface heating process of Ti/steel composite plate by molecular dynamics simulation and experimental research.The specific research contents are as follows:Based on molecular dynamics simulation,a reasonable integration algorithm and potential function were selected to establish a high temperature diffusion model of irontitanium interface,and its stability and reliability were verified.Firstly,the influence of diffusion temperature and time on the diffusion behavior at the interface was studied,and the diffusion coefficient and diffusion activation energy of iron and titanium atoms at the interface were calculated by using the root mean square displacement curve and Einstein equation.Then,by analyzing the radial distribution function and shear strain of the diffusion region,the interface crystal structure evolution and atomic bonds and processes during the atomic diffusion process are characterized.Finally,the diffusion trajectories and distribution positions of titanium atoms and iron atoms in the matrix were marked and tracked to reveal the microscopic diffusion mechanism of the two atoms at the interface.In order to further understand the interfacial diffusion behavior,the molecular dynamics simulation of the heating process of Ti/steel composite plate is verified and supplemented.The cold-rolled Ti/steel pre-composite plate was heated by changing different heating process parameters,and the influence of heating time and temperature on interface element diffusion and microstructure evolution was analyzed.Secondly,the tensile properties and microhardness of the cold rolled Ti/steel pre-composite plate after heating and diffusion were measured,and the influence mechanism of the interface on the mechanical properties of the Ti/steel composite plate was expounded.Finally,combined with XRD analysis and thermodynamic theory,the formation process and evolution law of the interface phase of Ti/steel composite plate were discussed.The results show that increasing the heating temperature can effectively enhance the intensity of element diffusion at the interface,and prolonging the heating time can ensure the full diffusion of interface elements.However,too high temperature or too long time will destroy the interface structure.Studying the influence mechanism of diffusion time and temperature on the diffusion of interface elements has important guiding significance for further design and optimization of the heating process of Ti/steel composite plates.