Issue 77

C. Bleicher et alii, Fracture and Structural Integrity, 77 (2026) 265-280; DOI: 10.3221/IGF-ESIS.77.16

N OMENCLATURE

A 5 [-] 

Elongation at fracture

Al

Aluminum

Fatigue strength exponent Fatigue ductility exponent

b [-] c [-]

Cu

Copper

d [mm] E [GPa]

Diameter of the specimen

Young’s modulus Test frequency Test frequency

f

f [Hz]

Fe

Iron

k [-] k* [-] K f [-] K t [-] M [-] N [-] n‘ [-] N f [-] Mn

Slope of the SN curve in the medium cycle fatigue range Slope of the SN curve after the knee point

K‘ [MPa]

Cyclic hardening coefficient Fatigue notch factor Stress concentration factor Mean stress sensitivity

Manganese

Number of cycles

Cyclic hardening exponent Number of cycles to failure

Ni

Nickel

N i [-]

Number of cycles to crack initiation Number of load cycles at the knee point number of cycles at the knee point

N k

N k [-]

Limit number of cycles limit number of cycles probability of survival cyclic yield strength

N lim

N lim [-] P S [%]

R‘ p0,2 [MPa]

R m

Tensile strength Yield strength

R p0.2

R s

Load ratio under stress

load ratio under constant amplitude loading for strain and stress

R ε , R  [-]

Tin

Sn

T σ [-]

Scatter band in stress direction

Scatter band in strain direction for the plastic strain-life curve Scatter band in strain direction for the elastic strain-life curve

T  ,pl T  ,el Zn

Zinc

Temperature

 C  ε ’ f [m/m] ε a,e [%] ε a,p [%]

fatigue ductility coefficient

elastic strain plastic strain

ε a,t [%]

total strain under constant amplitude loading

standard deviation



fatigue strength coefficient

 ’ f [MPa]  a,n,k [MPa]

nominal stress amplitude at the knee point

Nominal stress amplitude at the limit number of cycles

 a,n,Nlim [MPa]

R EFERENCES

[1] Pavesi A., Bandiera M., Mancini A., Tsyupa B., Bonfanti A., Casari D., Barella S., D'Errico F., Bertasi F. (2023) Effect of anodizing on high cycle fatigue behaviour of cast AlSi8Mg-T6 alloy, International Journal of Fatigue, 176, 107836, DOI: https://doi.org/10.1016/j.ijfatigue.2023.107836

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