Abstract: The macroscopic deformation of double vertical explosive welded composite plate increased the manufacturing cost and even caused the product to be scrapped.In this paper,the one-dimensional dispersion of detonation products was analyzed by using the characteristic line method,and the distribution curves of explosive impulse in X and Y directions of the plate were obtained.In order to explore the influencing factors of macroscopic deformation of TA2/Q235B composite plate,four groups of double vertical explosive welding comparison tests were conducted.Under the condition that the mass ratio was 1∶0.36∶3.19,the deformation law of flexible sand and soil protection followed the impulse distribution curve,and the existence of concave and convex pits was observed in the composite board when rigid stone wall protection was adopted; under the condition that the charge mass ratio was 1∶0.4∶7,the composite plate mainly presented internal bending deformation due to its high strength,and the macro deformation of large area composite plate was reduced by adopting rigid + flexible comprehensive protection device.The macroscopic deformation of the plate was influenced by the charge mass ratio,the characteristics of the protective device and the action impulse of the explosive,and the influencing factors of these three factors decreased in turn.The macroscopic deformation caused by double vertical explosive welding can be further solved by appropriately reducing charge mass ratio,optimizing protection device and popularizing double vertical explosive welding + rolling technology.