ESDU 78016:2013

ESDU 78016 discusses methods for improving the fatigue strength
and uses results of constant-amplitude fatigue tests from the
literature to show their effectiveness. The effect of changing the
stress concentration by improving the weld shape by grinding or
tungsten inert gas welding is shown graphically by plotting
alternating stress against endurance for longitudinal and
transverse welds compared respectively with data from ESDU 75016
and 76007 for untreated welds. The effect of introducing
compressive stresses by shot-peening is similarly compared with the
same ESDU data for untreated welds. These cases all use results
with zero mean stress. For longitudinal welds stress relieved by
heat treatment, the fatigue strength at three different mean
stresses is compared graphically with the untreated weld data from
ESDU 76007, while for longitudinal welds treated by spot-heating or
spot-pressing only zero mean stress data are available for
comparison with data from ESDU 76007. A table summarises the
improvements achieved by the various methods.