FATIGUE CRACK GROWTH BEHAVIOUR OF BASE METAL, WELD METAL AND HEAT AFFECTED ZONE OF ALLOY 800 AT 823 K

Constant load amplitude fatigue crack growth (FCG) experiments were performed at 823 K in air environment on compact tension specimens of base metal, weld metal and heat affected zone (HAZ) of Alloy 800 machined from pipes of 197 mm diameter and 23.5 mm wall thickness. The test frequency of 5 Hz and stress ratio of 0.05 was used for FCG testing. In all test conditions, FCG behaviour of Alloy 800 was successfully described using linear elastic...