Mg alloy scaffold with spherical/cubic hybrid pores for orthopedic repair

•Mg-Zn-Ca alloy scaffold with spherical/cubic hybrid pores was prepared.•The structure–property relationships were evaluated by experiments and theoretical analysis.•The Mg alloy scaffold was adaptive to the cancellous bone in terms of mechanical properties.•A flowing-assisted chemical conversion treatment was introduced for surface modification. Biodegradable Mg-based scaffolds are regarded as potential bone tissue engineering materials for a promising approach to bone repair. In this work, the spherical/cubic hybrid pore-forming agents were introduced to prepare a porous Mg-based alloy scaffold by the negative salt pattern molding method. The porous Mg-Zn-Ca alloy scaffold containing spherical/cubic hybrid pores exhibited a porosity of about 68.60 % and a surface area ratio of about 7.88 cm2/cm3. The compressive elastic modulus was about 0.32 GPa and the compressive strength was about 4.22 MPa, close to cancellous bone. However, the rapid degradation of Mg alloy scaffold was inadaptive to orthopedic repair. Thus, a calcium phytate coating was prepared on the Mg-based scaffold for surface modification to retard rapid corrosion.