ESTIMATOR TYPE AND POPULATION-SIZE FOR ESTIMATING THE WEIBULL MODULUSIN CERAMICS

Analysis of fracture data in ceramics can be made by applying probabil istic theories. In order the fracture probability to be expressed an e stimator must be used. For economic reasons it is also necessary, the population size for estimating the shape ceramic parameter, to be foun d. In the present work a number of estimators and sets of different sa mple populations of kaolin ceramics are tested against the stability o f the weibull shape parameter. The 2-parameter and 3-parameter Weibull functions and the Neville function were compared for best fitting of results. It seems that modulus remains almost constant in the range of the specimen numbers tested and a minimum number of about 30 specimen s is acceptable for reliability predictions at least for the examined type of ceramic. (C) 1998 Elsevier Science Limited All rights reserved .