ESDU 20004:2019

INTRODUCTION

This Data Item presents a guide to the fatigue data offered in the Stress and Strength of Components (SASC) Series at ESDU.

A useful introduction to general fatigue terms used in the fatigue-based Data Items in the SASC Series is given in ESDU 70016. ESDU 71009 summarises some general design principles that may be considered to minimise the risk of fatigue failure.

In Section 2, the fatigue data available in the SASC Series is briefly reviewed. The data presented in the SASC Series are derived from either a constant-amplitude stress-life fatigue test or from a strain-life fatigue test (see ESDU 04022 for an introduction to strain life (low cycle) fatigue). During fatigue testing it is important to consider the effect of temperature, testing environment and other factors such as fretting (see ESDU 90031) that may have a detrimental effect on fatigue strength. Furthermore, there are many approaches that can improve fatigue strength such as using surface treatments (see ESDU 89031 for further details). Most of the data summarised in this Item are from tests carried out on samples of small dimensions. However it must be remembered that the relative size and scale of the test specimens can influence fatigue strength, see ESDU 87016.

Most of the fatigue data given in the SASC Series are reported for steel and aluminium test samples but there is also a limited amount of data available regarding the fretting of titanium. A guide to the fatigue strength of welded joints is given in ESDU 86013. Once fatigue data have been obtained, ESDU 97024 can be used to plot curves through the fatigue data to aid the interpretation of the data.

A list of the Data Items offering fatigue data in the SASC Series is given in Section 3. In Section 4 a summary of the data is presented.