EVALUATION OF SCATTER IN STATIC STRENGTH OF CARBON/POLYIMIDE LAMINATES

The objective of this study is to evaluate common scatter parameters from many data sets of small sample sizes. Especially, the methods to average the estimates of the coefficient of variation are proposed. Static tests for smooth and circular hole notched specimens made of T-800H/PMR-15 carbon polyimide laminates yielded various static strengths at four temperatures. The mean and the averaged estimates of the standard deviation and coefficient of variation as functions of temperature are calculated from the obtained data and evaluated. The distributional form of tensile strength in the smooth specimens at room temperature is discussed.