45S5 bioactive glass-ceramic coated magnesium alloy with strong interfacial bonding strength by “superplasticity diffusion bonding”

• A strong interfacially bonded 45S5 glass-ceramic coating was fabricated on AZ31B alloy.
• Applying appropriate pressure can enhance the interfacial bonding strength.
• Large crystallization is unfavorable for the improvement of adhesion strength.

A strong interfacial bonded 45S5 glass-ceramic coating was fabricated on AZ31B magnesium alloy using a sol−gel dip-coating technique followed by thermal treatment at temperature of 480 °C and different Ar pressures. When the pressure was 0.6 MPa and held for 90 min, the bonding strength reached 26.8 MPa, much higher than that of samples thermally treated at the same temperature without any pressure. The strong interfacial bonding strength is mainly attributed to the solid solution reaction accelerated by the atomic diffusion due to the pressure.