Effects of strontium-substitution in sputter deposited calcium phosphate coatings on the rate of corrosion of magnesium alloys

Magnesium (Mg) alloys have significant potential for use as bioresorbable orthopaedic implant devices due to their controllable mechanical properties and an ability promote new bone growth. However, difficulty lies with controlling the rate of corrosion in physiological conditions ensure load-bearing capability device is maintained required period time, specifically until adequate quantity tissue formed. In this work, RF magnetron sputtering has been used create calcium phosphate (CaP) strontium-substituted (SrCaP) thin film coatings on two Mg alloy systems (denoted WJK ZEWX) that formulated fabrication fracture fixation devices. A 14-day static-dynamic immersion study simulated body fluid (SBF), shows uncoated substrates had a 4.04 ± 0.15 millimetres per year (mmpy), which was reduced 3.22 0.17 mmpy application CaP coating, 2.92 0.05 SrCaP coating. Uncoated ZEWX 3.36 2.98 0.19 2.79 0.03 mmpy, coatings, respectively. Whereas sputter-deposited completely dissolve SBF over immersion, presence at outset significantly decreases both alloys, compared values substrates. Successful incorporation Sr within coating offers improved bioactivity respect directing cell response tissue.