Numerical evaluation of the impact of introducing heterogeneous structures into the REBCO layer on fracture behavior under tensile strain

•Heterogeneous structures exert a significant suppressive effect on crack propagation, consequently elevating the tensile strength of the REBCO tape.•The initial crack location plays a crucial role in determining the efficacy of heterogeneous in inhibiting crack propagation.•Adjusting the distribution of heterogeneous structures allows for the enhancement of mechanical strength while minimizing critical current degradation.