Research On The Interfacial Features And Formation Of 0Cr13/Q235 Composite Maded By Explosive Welding

As a low-cost,and easy-to-use technology,explosive welding is widely used in the preparation of metal composite,which can generally realize the connection between dissimilar metal,and the obtained combination is very effective.Stainless steel(SST)/carbon steel(CS)explosive-welded composite realize the combination of the corrosion resistance of the SST and the high strength of CS,which is widely used in chemical and pressure vessels production.It is of great significance to study the bonding mechanism and dynamic process of explosive welding to provide theoretical basis for optimization of process parameters and obtain composite with higher quality.In this paper,the interface characteristics and forming mechanism of 0Cr13/Q235explosive-welded composite were studied.(1)The two-dimensional simulation of the explosive welding process of0Cr13/Q235 composite was carried out based on the Smoothed Particle Hydrodynamics(SPH)method.The simulated wavy interface was consistent with the actual interface.The effects of different closing velocities and different tilt angles of the flyer plate on the wavey interface were studied.The results showed that if the closing speed is large than lower limit of the explosive welding,the interface is better when the closing speed is samll,the waveform of the interface is uniform and large votrex,voids and cracks will not be generated.Appropriate tilting of the flyer plate helps to prepare a satisfied wavy interface,and the waveform characteristics are more obvious as the tilt angle of the flyer plate increases.(2)The wavy interface of 0Cr13/Q235 explosive-welded composite was observed by metallographic microscope,SEM,EDS and Vickers hardness testing.The results showed that the molten metal layer,and votrex was formed at the interface of the0Cr13/Q235 composite.The grain size on the Q235 side is larger and the microstructure exhibited as equiaxed crystal.On the side of 0Cr13 is more deformed,the grain size is much finer,and there displayed elongated grains.A slight degree of elemental diffusion occurred at the 0Cr13/Q235 interface(within a distance of 5 ?m).The microhardness test results showed that a large degree of work hardening produced at the metal melted layer.(3)According to the simulation of explosive welding process of 0Cr13/Q235 composite,the dynamic process of interface waveform formation is analyzed.The results showed that at the initial stage of explosive welding,a flat interface was formed between 0Cr13 and Q235,and then a wavy interface was formed.The formation of waveform is similar to Bahrani mechanism and the collosion occurred in microseconds.The plastic deformation was mainly concentrated at the interface.The physical state near the collision point was of high pressure,high temperature and high strain rate.Difference in the structure on the two sides of the interface was due to the different physical states and deformation during explosive welding.(4)The effects of different heat treatment temperatures on 0Cr13/Q235 explosive welded composite was studied.The results showed that the work hardening at the interface was improved after heat treatment,but if the temperature was too high,brittle carbide phase would be formed near the interface,which could adversely affect the corrosion resistance of the 0Cr13/Q235 bonding zone.