This study aims to implant materials, especially stainless steel (SS), which are widely used. However, because SS is not inherently biocompatible, the surface of SS implants is usually coated with biocompatible materials to improve biocompatibility.
In the present study, a hybrid chitosan/strontium chloride/magnesium oxide/hydroxyapatite coating was developed on 316L SS via electrophoretic deposition (EPD). Design experiments were used to create an orthogonal array of the L9 Taguchi approach for boosting the essential EPD parameter range, which is voltage (15–35 V), deposition time (1–5 min) and coating temperature (25–40 °C).
The main finding revealed that a 25-volt voltage, a 5-minute duration and a temperature of 25°C are the optimal conditions. It produced a coating thickness of 132 µm and an adhesion force of 35.89 N, demonstrating an enhancement of more than 65% compared to other process groupings. According to X-ray diffraction and field emission scanning electron microscopy (FESEM) results, a homogenous crystalline MgO/HAp-rich deposit with enhanced surface integrity was formed. The results indicated that corrosion resistance (evaluated in simulated body fluid and simulated mouth saliva) is mainly controlled by the presence of the coating layer. Maximum coating efficiencies were 95.5% and 98.5% for SBF and SMS, respectively, at a higher level of coating thickness and adhesion force.
The novelty of this research is a functional bioactive coating, with deposition parameters quantitatively linked to adhesion strength, coating thickness and corrosion resistance. The coating of this hybrid composite coating is considered well-suited for biomedical applications, providing protection against both mechanical and chemical attacks, offering novel insights for bio-implant applications.
