Regularities in macro- and micromechanisms of fatigue crack growth in a bimetal of continuous caster rolls

• Stage-like nature of the fatigue crack propagation in the bimetallic specimen into macro-, meso-, and micro-levels is determined.
• It is found that 10 s hold under the maximum loading (trapezoidal cycle) increases the fatigue crack growth rate by 3–8 times.
• The step of striations is 60% lower than the macrorate.