Influence of Residual Stress on Mechanical and Tribology Behaviors of Calcium-Phosphate Coating on Commercially Pure Titanium via Integrated Electrospinning and Rapid Heating and Cooling Process

This study focuses on the role of residual stress in the tribological behavior of calcium-phosphate (CaP) coating on titanium (Ti) substrate. The CaP coating was applied using an integrated electrospinning and rapid heating and cooling (EMRHC) process. The residual stress over half and full done EMRHC process was measured by x-ray method. The substrate and coatings were characterized using a field emission scanning electron microscope equipped with the energy-dispersive spectroscope, Vicker's microhardness, atomic force microscopy, and x-ray diffractometer techniques. It was found that the preliminary hydroxyapatite on the Ti substrate was exchanged with α-TCP, CaO, TiO2, CaTiO3, and Ti5P3 over the EMRHC process. The results also showed that the tensile + 591 ± 89 and compressive − 189 ± 42 MPa residual stress remained on the surface over the half and full done EMRHC process, respectively. The hardness, Young module, and ultimate tensile strength of both samples were enhanced significantly by the EMRHC process. The tribology of samples was comprehensibly evaluated in a dry and simulated body fluid solution. The CaP coating prepared by the full-EMRHC process showed the lowest wear rates in comparison with the others due to the compressive residual stress. The coefficient of friction of CPTi coated by EMRHC was significantly reduced when exposed to the SBF solution. Our findings revealed that EMRHC is a promising method to fabricate the Ti implant with higher mechanical properties.