Modeling the healing of damage of metal by high-energy pulsed electromagnetic field

The processes transformation of defects such as the intergranular micro-cracks are investigated. These processes occur in the material under the processing of metal samples with high-energy pulsed electromagnetic field inducing in the material a short pulse of high density electrical current. Investigation on basis of numerical coupled model of the impact of high-energy electromagnetic field on the pre-damaged thermal elasticplastic material with defects are carried out. The model accounts for melting and evaporation of metal and dependence of its physical and mechanical properties on temperature. Equations is solved numerically by finite elements method with adaptive mesh using on base of alternative Euler-Lagrange's method. Calculations has shown, that welding of crack and healing of micro-defects under treatment of short pulse of current are took place. Healing occurs by simultaneous reduction in length, the ejection of the molten metal into crack and closing of micro-crack shores. For macroscopic description of the healing process the material healed and damage parameters are entered. Healing of microcracks leads to the reduction of damage of the material. Shapes of microcracks practically does not affect on dependences of healed and damage from time under treatment of current pulse. These changes are affected by value of initial damage and initial length microcrack only. The dependences of healed and the damage from the time will be practically same for all different shapes of microdefects, provided that initial lengths microcracks and initial damages are equal for these different shapes of defects. Simple approximate piecewise-linear dependences of damage and healed from time and the initial damage are obtained.