Vol.3, No 13, 2003 pp. 533-552
UDC 539.219.2 620.1
FAILURE METHODOLOGY OF MODE-II LOADED
CRACKS
Jörg F. Kalthoff
Experimental Mechanics, Ruhr-University Bochum, 44780 Bochum, Germany
e-mail: Joerg.F.Kalthoff@ruhr-uni-bochum.de
Various aspects of the failure behaviour initiated from mode-II loaded
cracks are discussed: validity criteria and minimum size specimen requirements
for measuring the fracture toughness KIIc; energy balance of the process
of initiation of kinked cracks including compressive notch tip stress concentrations;
failure mode transition from tensile cracks to adiabatic shear bands at
high loading rates; loading rate dependence of the dynamic fracture toughness
KIId in the regime of failure mode transition. Findings of studies on these
subjects are presented and implications of the results for practical applications
are discussed. The failure behaviour of mode-II loaded cracks is found
very different and far more complicated than of mode-I loaded cracks, generalizations
from mode-I to mode-II can therefore be severely misleading.
METODIKA LOMA OPTEREĆENIH PRSLINA MODA
II
Razmatraju se različiti aspekti ponašanja pri lomu koji započinju iz opterećenih
prslina moda II: kriterijumi validnosti i minimalni prohtevi veličine uzorka
za merenje žilavosti loma KIIc; ravnoteža energije procesa inicijacije
uvojitih prslina uključujući kompresivne koncentracije napona vrhova ureza;
prelaz moda loma sa tegljivih prslina na adijabatske smicajne trake pri
visokim stopama opterećenja; zavisnost stope opterećenja dinamične žilavosti
loma KIId u režimu prelaza moda loma. Prikazani su nalazi studija na ove
teme, i razmotrene implikacije rezultata za praktične primene. Utvrdjeno
je da je ponašanje pri lomu opterećenih prslina moda II veoma drugačije
i daleko složenije od opterećenih prslina moda I, tako da uopštavanja sa
moda I na mod II mogu dovesti do jako velikih grešaka.
