Statistical design: wear modes

Abstract

From the physical nature of wear behaviour developed in section 6.3, a very simple design technique can in principle be formulated for all wear processes. The life calculated using an s−N _F curve in conjunction with any damage law is N _F . So, instead of using the standard median s−N₅₀ curve (50 per cent failures) to calculate N₅₀ and relating that to N _F by empirical factors, the s−N _F curve corresponding to the required F% failures can be derived as described in the previous chapter and used directly in design without any factor. In essence, statistically derived input data are being used in an otherwise conventional design methodology.