Field-Induced Phenomena in Electrical Insulation.
Abstract
Based on the results obtained in the combined electrical and thermal aging studies (previously reported in the Second Annual Scientific Report), the investigations were extended to include the effect of morphology on the breakdown strength of polymers. Earlier studies that dealt with this topic were examined. Isotactic polypropylene plaques were prepared by melt-pressing beads of the polymer in a hydraulic press. Samples of widely differing morphologies were produced by subsequent annealing (after quenching in cold water) or isothermal cyrstallization, under a variety of conditions. These samples were than characterized as to their crystallinites and crystallite thicknesses by a number of techniques including wide-angle X-Ray diffraction and density measurements. The AC breakdown voltages of these samples at three temperatures (7 C, 23 C, and 45 C), were determined using standard procedures. Based on the experimental results, the breakdown mechanisms that were operative are identified. Recommendations for future research are made at the end of the report.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1986
- Accession Number
- ADA177215
Entities
People
- J. R. Laghari
- R. K. Gupta
- W. J. Sarjeant
Organizations
- University at Buffalo