Carmo Lança
Assistant Professor / Researcher /-/ Materials Science Dept. /-/ Professora Auxiliar / Investigadora /-/ Dept Ciências Materiais /-/ I3N/Cenimat
The dielectric breakdown of thin films of low-density polyethylene (LDPE) electrically aged in an aqueous solution of NaCl under an AC electric field was investigated. A two-parameter Weibull function was used for the dielectric breakdown time to failure. The probability of failure for a sample was obtained by the White method for progressively censored data. Samples aged at different temperatures were compared. The results show that initially the samples aged at lower temperature (approximate to25degreesC) are more prone to fail, while those aged at higher temperature (50degreesC) fail at longer times. This was attributed to a competition between oxidation and diffusion.
2nd International Materials Symposium APR 14-16, 2003 Caparica, PORTUGAL