Influence of processing parameters on electrical insulation properties for epoxy-resin materials-an investigation by experiment and finite element analysis simulation

This paper discusses the influence of the speed of the heating process upon epoxy casting of special test specimens on generating mechanical stresses inside a mold. Higher speed leads to higher temperature gradients and therefore to larger internal stresses which by itself promotes cracking in the solid epoxy material. As a consequence of that, the partial discharge inception voltage is decreased. Finite element analysis shows that differences in the thermal expansion coefficient of the materials in the mold together with the absolute temperature level are responsible far the degree of mechanical stresses and finally for the partial discharge behavior of the solid product.