Abstract:
Creep crack
growth rates are investigated in compact tension specimens of
cast HK40 steel at 830, 850, 871 and 890℃; Apparent activation
energies for creep and creep crack growth are measured in the
temperature range 830 890℃; Over limited ranges of stress and
temperature, the values of the two energies are close. The creep
crack growth behavior of cast is different from that of the
creep damaged specimens. The creep crack growth rate of cast
specimen increases more quickly than that of creep damaged
specimens with the increase of the stress intensity factor. The
fine secondary carbides make the creep crack growth rate
increase and the time to rupture shorten.
Key words:
Creep crack growth Activation
energy Microstructure Cavity Creep damage Stress intensity
factor
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