抄録
Fatigue crack growth rates in the base metal and welds of HT80 steel welded joints were evaluated at temperatures ranging from room temperature down to 93 K. For the welds, the crack growth rates between room temperature and 173 K were dominated by residual stresses rather than temperatures. As temperatures decreased below 123 K, the crack growth rates of the base metal and welds increased markedly because of cyclic cleavage during striation growth. The crack growth rates of the welds were correlated with an effective stress intensity factor range, ΔKeffR, which was estimated by superposition of the respective stress intensity factors for the residual stress fields and for the applied stresses when the crack growth was dominated by striation formation.
