Page 415 - Biaxial Multiaxial Fatigue and Fracture

A Multiarial Fatigue Lge Criterion for Non-Symmetrical and Non-Proportional Elasto-Plastic ... 399

2 I. Simbiirger, A. (1 975). Festigkeitsverhalten zaher Werkstoffe bei einer mehr-achsigen,
phasenverschobenen Schwingbeanspruchung mit korper-festen und veranderlichen
Hauptspannungsrichtungen. LBF FB-121, Fraunhofer-Institut fiir Betriebsfestigkeit
(LBF), Darmstadt.

NOMENCLATURE

D, Constants used to define the material function K
Uniaxial fatigue strength exponent
Uniaxial fatigue ductility exponent
Axial elastic and secant modulus
Logarithmic error index
Cyclic hardening coefficient

Cyclic hardening exponent
Experimental and calculated fatigue life
R Cycle ratio
t Time
GB%P Material constants
Total equivalent strain

Gq. a Equivalent strain amplitude
4 Uniaxial fatigue ductility coefficient
Yn 12 Shear strain vector in each interference plane of normal n (p, 29)

E,,
E,, E~, E,, E,, E, Strain tensor components
EX." 3 &",U 3 5." Normal strain amplitudes
Y(294 Shear strain in an interference plane 29 at time t
Ya(zrt) Shear strain amplitude in an interference plane 29
z',.alim Arithmetic mean value of ya (4)

~en,inst (1) Instantaneous effective shear strain at time t
Yen,", Effective shear strain alternating and mean component
Y2 Total effective shear strain
Yx,,, Y,,,,, Yzr.o Shear strain amplitudes

K Material function
K',/ Elastic material constant