A biodegradable Mg/MgO composite coating was deposited onto AZ31B magnesium alloy by high-velocity suspension flame spraying technique using nano-sized MgO and micron-sized Mg powders. Phase constitution, microstructure, mechanical property and corrosion behavior of Mg/MgO composite coatings with different Mg/MgO ratios were investigated. Mg/MgO composite coatings with different Mg/MgO ratios presented rough and porous surfaces with typical features of solid-fluid co-deposition and exhibited well bonding coating/substrate interfaces with some pores within the coatings. Mg/MgO composite coatings prepared by co-deposition of Mg/MgO mixed powder were mainly composed of Mg rather than MgO indicating superior deposition of Mg. Microhardness, elastic modulus and tensile strength of Mg/MgO composite coatings were influenced by the Mg/MgO ratio. Mg/MgO composite coatings presented a limited corrosion protection for Mg alloy substrate after immersion in Hanks’ simulated body fluid for different times. Corrosion behavior of Mg/MgO composite coatings was also discussed. This study proposed a strategy to prepare biodegradable Mg/MgO composite coating on metal substrates for potential applications in the implant field.

使用纳米级MgO和微米级Mg粉末，通过高速悬浮火焰喷涂技术在AZ31B镁合金上沉积了可生物降解的Mg/MgO复合涂层。研究了不同Mg/MgO比的Mg/MgO复合涂层的相组成、显微组织、力学性能和腐蚀行为。具有不同Mg/MgO比的Mg/MgO复合涂层呈现出具有典型固液共沉积特征的粗糙多孔表面，并表现出良好的涂层/基材界面，涂层内有一些孔隙。Mg/MgO 混合粉末共沉积制备的 Mg/MgO 复合涂层主要由 Mg 组成，而不是 MgO，表明 Mg 的沉积性能优越。Mg/MgO复合涂层的显微硬度、弹性模量和拉伸强度受Mg/MgO比的影响。在汉克斯模拟体液中浸泡不同时间后，Mg/MgO 复合涂层对镁合金基体的腐蚀保护有限。还讨论了 Mg/MgO 复合涂层的腐蚀行为。该研究提出了一种在金属基材上制备可生物降解的 Mg/MgO 复合涂层的策略，以用于植入领域的潜在应用。