ESDU 04022:2012

Available as part of the ESDU Series on Stress and Strength and
on Fatigue – Endurance Data. For information on all ESDU validated
engineering data please contact us using the details on the
preceding page.

ESDU 04022 introduces the basic equations of low-cycle fatigue
analysis, and some of the limitations of their usage. Both the
strain-life relationship (otherwise known as the Coffin-Manson
equation) and the cyclic stress-plastic strain equation are
derived. The effects of mean stress on the strain-life relationship
and the methods of correcting for these proposed by Morrow, Manson
and Halford are discussed, as are the transition fatigue life and
the Bauschinger effect. The cyclic hardening and softening
behaviour of metallic materials during cycling and their stress and
strain response at different test temperatures (including the
effects of oxidation, creep-fatigue interaction, dynamic strain
ageing, cold creep or "time-dependent plasticity", and martensite
transformation during cycling) are also considered. The Data Item
includes a section on low-cycle fatigue testing procedures and the
pit-falls and uncertainties encountered during such testing.
Procedures to determine the onset of failure and guidance on the
design of LCF test pieces are presented with reference to
contemporary standards. In addition, the Item discusses methods of
estimating low-cycle fatigue properties that can be used when
limited data are available; two comprehensive examples which
illustrate the use of these methods are provided.