Formation mechanism of Ca-deficient hydroxyapatite coating on Mg-Zn-Ca alloy for orthopaedic implant

- Microstructure evolution of Ca-def HA coating was systematically investigated.
- Poor crystalline Ca-def HA has been formed at the deposition time of 5 min.
- Reasons for direct formation of Ca-def HA coating on Mg-Zn-Ca alloy are discussed.