Some Estimations of Tolerance Bands of S-N Curves

Abstract

A precise determination of tolerance bands of S-N curves is quite difficult problem; therefore simple approximate constructions of these bands are often used. Castillo et al. suggested a sophisticated and at the same time easy procedure for their estimation which, however, needs a special type of regression function for describing S-N curve. This type of regression function called the Castillo function is suitable only for high-cycle fatigue region close to fatigue limit. The paper focuses on other regression functions used in the Castillo procedure, namely on the Kohout and Vechet function and the Stromeyer function.