Composite hydroxyapatite–PTFE coatings on Mg–Mn–Ce alloy for resorbable implant applications via a plasma electrolytic oxidation-based route

• The coatings containing HA were obtained on Mg–Mn–Ce alloy by PEO method.
• PEO layers were post-treated using SPTFE powder.
• Corrosion properties of the coatings in Hank's and 3% NaCl solutions were studied.
• Composite polymer containing coatings show superior anticorrosion properties.

Multifunctional corrosion resistant and bioactive coatings containing hydroxyapatite Ca10(PO4)6(OH)2 and magnesium oxide MgO were obtained on Mg–Mn–Ce alloy by plasma electrolytic oxidation. The phase and elemental composition, morphology and anticorrosion properties of the coatings were investigated. The PEO layers were post-treated using Forum® superdispersed polytetrafluoroethylene powder, which caused a considerable reduction of the magnesium alloy corrosion rate (>4 orders of magnitude). In particular, the polarisation resistance has increased, as a result of such duplex treatment, by five orders of magnitude. The composite coatings are considered promising to induce bioactivity and control corrosion degradation of resorbable Mg implants.