CALCULATION OF THE STRESS-STRAIN STATE OF THE CLADDING LAYER DURING CLADDING (WELDING) BY EXPLOSION

Abstract

Purpose. Development of a mathematical model of the process of elastoplastic deformation of the cladding layer of a layered workpiece during welding (cladding) by explosion with the formation of the objective function of optimal deformation and establishing a relationship between the parameters of welding (cladding) by explosion and the shear bond strength of the layers and the wear resistance of the cladding layer. Methodology. The solution to the problem of elastoplastic deformation is carried out using the equations of the flow theory and the nodal calculation scheme. The required deformation values are determined at the nodal mass points of the computational grid. At each moment of time, the positions of the nodes of the cladding workpiece, thrown under loading by a traveling pressure wave, are de-termined. Deformations and their intensity are determined by the position of the nodes. The task of determining the re-quired parameters of explosion welding (cladding) is reduced to the task of mathematical programming. The objective function is minimized on a family of curves, the arguments of which are the explosion welding (cladding) parameter and the welding gap. The interaction of the cladding workpiece with the pressure wave generated during the detonation of the explosive is determined by the dependences of the pressure of the detonation products, the mass velocity of the cladding workpiece and the shock wave velocity at the moment the shock wave reaches the free surface on the parame-ters of the explosion cladding (welding) with subsequent calculation of the stress-strain state of the workpieces. Accord-ing to the optimal parameters of explosion welding (cladding), a probabilistic assessment of the shear bond strength of the layers is carried out. If the strength is insufficient, the parameters are adjusted. Findings. As a result of numerical modeling, the calculation of the deformed state of the projectile is carried out. The parameters of explosion welding (cladding) are determined, at which the intensity of deformations of the cladding layer corresponds to the limit uniform ones. Based on the obtained parameters of explosion welding (cladding), the calculation of the shear strength of the layer joint was performed. Originality. For the first time, a model has been developed for the optimal deformation of the cladding layer during explosion welding (cladding) of wear-resistant compositions. The target function and the optimal process parameters have been established. A method is proposed for calculating the weighting coefficients of the objective function for multi-criteria multilevel optimization. Practical value. Recommendations for industrial application were developed and modes of explosion welding (cladding) were tested to obtain wear-resistant compositions of aluminum alloy with carbon steel.