hirose
data frame has 44 rows and 3 columns.PET film is used in electrical insulation. In this accelerated life test the failure times for 44 samples in gas insulated transformers. 4 different voltage levels were used.
data(hirose)
Hirose, H. (1993) Estimation of threshold stress in accelerated life-testing. IEEE Transactions on Reliability, 42, 650--657.