Experiment Weibull statistics

CF studies have not provided such information, often because of time-intensive slow frequency experiments and the many important variables. A sense of the variability in CF data is portrayed by the extensive HCF results collected for C-Mn and alloy steels in marine environments [58]. The distribution of HCF lives at a given stress range was analyzed based on Weibull statistics applied to a database of 30 000 points for steels in benign environments [82]. While instructive, these statistical results are not necessarily relevant to high-cycle CF where electrochemical reactions introduce additional variability. 

To measure the dielectric strength, a flat specimen is exposed to an increasing electrical field till a progressive current increase indicates when the critical field strength has been reached. Since electrical breakdown is a statistical event, multiple experiments must be performed and evaluated, typically using the Weibull distribution (Weibull 1951). Figure 12 presents an example. 

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