Forming and propagation of the cracks initiated with electric explosion of wires in polymer materials

Abstract

Electrical-physical techniques of intensive mechanical action based in particular on the phenomenon of electric explosion of wires attract more and more attention as methods of high-rated deformation and fracture of polymer spacemen such as Poly(methyl methacrylate) (PMMA), fluoropolymer, etc. Detailed investigation of forming of cracks and dependence between it and propagation of the shock waves through the sample appears to be mandatory for the understanding of the processes of high-rated loading of such polymers.The study investigates forming of the cracks under the action of the cylindrical shock wave initiated with the electric explosion of wire. Generation of such wave performed with short intensive high-voltage discharge through the thin wire placed along we axis of the sample and subsequent expansion of its vaporization products. Propagation of such cracks through cylindrical samples of PMMA and fluoropolymer with various rates of loading was discovered. The comparative specifications of the development of the cracks in PMMA and fluoropolymer were obtained. Threshold fracture parameters of tested materials were estimated for various rates of stress. Analysis of correlation between parameters of the wire explosion and cracks forming and development performed.