Crack propagation in ASTM A516 grade 70 steel under fatigue loading subjected to different temperatures

The values of C and m in the Paris law, da/dN = C ( Delta K) exp m , which change with temperature, are determined for ASTM A516 grade 70 steel. Values of m are nearly constant, whereas the values of C change considerably with temperature due to strain hardening effect. Fatigue crack propagation tests were performed on a 10 tonne MTS universal testing machine for temperature 23, 75, 150, 225 and 275 deg C on ASTM A516 grade 70 steel. Graphs. 3 ref.--A.R.