Deposition of calcium phosphate coatings using condensed phosphates (P2O74 − and P3O105 −) as phosphate source through induction heating

• Condensed phosphates (P2O74 −, P3O105 −) were used in induction heating method to deposit calcium phosphate coatings
• The phase, morphology and composition of related coatings were different from regular PO43 − based coating
• Possibility to prepare calcium phosphate coating using hybrid phosphate sources was investigated
• Condensed phosphates related coatings were deposited to both C/C composites and magnesium alloys

In present work condensed phosphates (P2O74 − and P3O105 −) were used as phosphate source in induction heating to deposit calcium phosphate coatings. The phase, morphology, and composition of different phosphate-related coatings were characterized and compared using XRD, FTIR, and SEM analyses. Results showed that P2O74 − formed calcium pyrophosphate hydrate coatings with interconnected cuboid-like particles. The as-deposited calcium tripolyphosphate hydrate coating with P3O105 − was mainly composed of flower-like particles assembled by plate-like crystals. The bioactivity and cytocompatibility of the coatings were also studied. Moreover, the feasibility of using hybrid phosphate sources for preparing and depositing coatings onto magnesium alloy was investigated.