پديد آورندگان :
ARABI H. نويسنده , SEYEDEIN S.H. نويسنده , SATTARI M. نويسنده , TABATABAEI N. نويسنده
چكيده لاتين :
Life assessment on the base ofgrain boundary creep cavitation of 1%Cr - 0.5%Mo low
alloy steel has been discussed in this paper. Since microstructural degradation is one ofthe most
important mechanisms that affects creep life, it is necessary to assess microstructural damage in
order to estimate the life. Microstructural damage within the grain boundaries is a continuous
phenomena starting from about the beginning of secondary stage of creep process. In this
research, the amounts of damage accumulation in the form of grain boundary cavitations for
various creep times up to the ends ofsecondary creep stage for each creep condition was found by
using quantitative metallography technique, i.e. image analyser. Then from the data obtainedfor
grain boundary area cavitated and number ofcavities per unit area, which was about linear as a
function of time for each of creep conditions, the amount of damage in the tertiary stage was
estimated for various times. Then a creep damage parameter was proposedfor the creep process.
Finally, having this damage parameter (OJ) and using continuum damage mechanics (CDM), a
new version ofRabotnov-Kachanov equation for tertiary creep rate was established.
