Plasma Electrolytic Oxidation (PEO) Coating on γ-TiAl Alloy: Investigation of Bioactivity and Corrosion Behavior in Simulated Body Fluid

Abstract

The effect of applied voltage (400, 450, and 500 V) on the microstructure, bioactivity, and corrosion rate of plasma electrolytic oxidation (PEO) coatings on γ-TiAl alloy was investigated. The microstructure and chemical composition of the achieved coatings were studied, along with their corrosion and bioactivity behaviors in simulated body fluid (SBF). The results demonstrated that the higher the coating's surface pore, the greater the number of suitable sites for the formation of hydroxyapatite with a spherical structure. The coatings applied utilizing 400, 450, and 500 V displayed 59.4, 96.6, and 145 Ω.cm2 as their inner layer electrical resistances, respectively. The findings of the biological examination revealed that Mesenchymal stem cells (MSCs) displayed more cytocompatibility and had a higher capacity for cell attachment in the PEO-coated sample than in γ-TiAl, as a result of better initial cell attachment made possible by the topography of the 500 V PEO coatings. The latter has significant potential to be employed in orthopedic applications.

Antibacterial Calcium Phosphate Coatings for Biomedical Applications Fabricated via Micro-Arc Oxidation

“…Surfaces of the samples Electrolyte 3 and Electrolyte 3 + ZnO differ from those observed from other sample groups and have a structure similar to a volcanic crater with a pore in the center, or the so-called “pancake-like” structure ( Figure 2 c,f). This structure has also been reported by other researchers [ 40 , 41 , 42 , 43 , 44 ]. The average pore diameter of Electrolyte 3 and Electrolyte 3 + ZnO coatings is about 3 µm ( Figure 2 c,f).…”

Study on Discharge Characteristics and Microstructural Evolution of PEO Coatings Based on an Al/Ti Tracer Substrate

“…The pore sizes on the coating surface gradually increased during the intermediate and late stages of discharge, accompanied by an increase in the number of large pores. The results are consistent with research conducted by Fatemeh Salahshouri et al [7]. Based on pore morphology, the larger pores can be classified into two: open-type pores induced by penetrating discharges, and "pancake" structured closed pores filled with re-discharged molten material (Figure 4(5)).…”

“…Metals such as Ti, Al, and their alloys are considered viable candidates for developing implantable materials in the medical field due to their satisfactory biocompatibilities. However, when these valve metals are exposed to corrosive physiological environments, coating techniques are required to create an oxide barrier layer on their surfaces [7]. Currently, methods such as the physical vapor deposition technique [8], cold spray technique [9], and ion beam-assisted deposition (IBAD) technique [10] can be employed to fabricate oxide coatings with high density and corrosion resistance.…”