Electrophoretic Deposition, Microstructure and Selected Properties of Composite Alumina/Polyetheretherketone Coatings on the Ti-13Nb-13Zr Alloy

Abstract

In this work, 45-120 μm thick, composite Al 2 O 3 /PEEK coatings were fabricated on the Ti-13Nb-13Zr alloy substrate using electrophoretic deposition. The anodic co-deposition of alumina and PEEK particles were investigated and discussed. The asdeposited coatings exhibited the uniform distribution of a nearly amorphous PEEK and crystalline alumina powders on the titanium alloy substrate. The morphology of PEEK in the coatings was changed by heating above the PEEK melting point from granular into dense coating matrix with semi-crystalline structure and spherulitic morphology. Scanning and transmission electron microscopy investigation of the coating microstructure revealed the presence of uniformly distributed Al 2 O 3 nanoparticles and their agglomerates within the PEEK matrix. Micro-scratch tests indicated that the coatings are characterized by excellent adhesion to the underlying substrate. The Al 2 O 3 /PEEK coatings significantly improved the wear resistance and reduced coefficient of friction of the Ti-13Nb-13Zr alloy during dry sliding, also in comparison with a polymer PEEK coated alloy. However, the wear resistance of the Al 2 O 3 /PEEK coated alloy during sliding in Ringer's solution was less than the PEEK coated alloy. The coatings increased the corrosion resistance of the alloy in Ringer's solution. The coatings were also found to be cytocompatible with Among biometallic materials, titanium alloys are increasingly used in medicine as implant material, due to their favorable mechanical properties, low elastic modulus, good electrochemical corrosion resistance and relatively good biocompatibility.1-4 Generally, β and near-β (including Ti-13Nb-13Zr) alloys have about 30% lower Young's modulus than that of two phase α+β alloys. 5 In the case of Ti-13Nb-13Zr alloy the elasticity modulus is reduced by Nb, 6 while Zr is neutral for both the α and β phase. The uses of all titanium alloys in applications exposed to abrasive wear in orthopedic surgery and traumatology, for example, in the head and acetabulum of hip endoprostheses, are limited. This is because of their relatively low hardness, low resistance to abrasive wear, high and unstable coefficient of friction (COF), severe adhesive wear and tendency to seize. 1,[7][8][9][10][11][12] Therefore, in order to improve the bio-tribological performance of titanium alloys, surface treatment is necessary.In recent years, polyetheretherketone (PEEK) coatings have often been applied as solid lubricant films in bio-tribosystems because of their notable wear resistance, corrosion resistance and self-lubricating capacity.13,14 PEEK, with a basic formula of (-C6H4-O-C6H4-O-C6H4-CO-)n, is a polyaromatic, semi-crystalline thermoplastic polymer exhibiting a superior combination of strength, stiffness, toughness and good biocompatibility. 15 Numerous studies have confirmed the successful clinical performance of PEEK for in vivo medical device applications, in orthopedic and spine implants. 13,[15][16][17][18] A number of studies [19][20][21] have also been conducted to d...

Curcumin-Containing Orthopedic Implant Coatings Deposited on Poly-Ether-Ether-Ketone/Bioactive Glass/Hexagonal Boron Nitride Layers by Electrophoretic Deposition

“…Afterward, the coefficient of friction (COF) remained stable for PEEK/BG and PEEK/BG/h-BN coatings. Few oscillations in the coefficient of friction of PEEK coatings were observed, which could be due to the nonuniform wear track in PEEK [44,45], as shown in confocal microscope images ( Figure 3). The oscillations in the wear test of PEEK coatings were repeated with each revolution of the disc.…”

Nanocomposite coatings obtained by electrophoretic co-deposition of poly(etheretherketone)/graphene oxide suspensions

“…However, it has also been used for purification, particle size reduction (in sizes ranging from nano-to micrometres), and development of specific particle morphology [32,33] and sonochemical synthesis [34][35][36]. Despite its benefits, TS has been rarely used in preparing PEEK suspensions for EPD [37][38][39] in comparison with bath ultrasonication [6,[40][41][42][43][44][45][46][47][48][49][50][51][52][53].…”

Improvement of the Ti-6Al-4V Alloy’s Tribological Properties and Electrochemical Corrosion Resistance by Nanocomposite TiN/PEEK708 Coatings

“…[11,16,17,19,[28][29][30][31] An alternative effective technique for the deposition of PEEK and PEEK-based coatings is electrophoretic deposition (EPD). [12][13][14][15][25][26][27][32][33][34][35][36] In previous studies of the authors, dense and well-adhered pure PEEK [32] and composite PEEK-based coatings [26,[33][34][35][36] have been successfully fabricated on titanium alloy substrates by EPD and subsequent heat treatment. Different reinforcing materials were used to enhance the PEEK properties, e.g., nanocrystalline Al 2 O 3 , [34] amorphous Si 3 N 4 nanoparticles (NPs), [35] and MoS 2 nanosheets.…”

“…[12][13][14][15][25][26][27][32][33][34][35][36] In previous studies of the authors, dense and well-adhered pure PEEK [32] and composite PEEK-based coatings [26,[33][34][35][36] have been successfully fabricated on titanium alloy substrates by EPD and subsequent heat treatment. Different reinforcing materials were used to enhance the PEEK properties, e.g., nanocrystalline Al 2 O 3 , [34] amorphous Si 3 N 4 nanoparticles (NPs), [35] and MoS 2 nanosheets. [36] Some inorganic NPs have been demonstrated to have the capability to reduce the friction and wear of PEEK.…”

“…In particular, Al 2 O 3 nanoparticle-reinforced PEEK coatings exhibited improved wear resistance in comparison with pure PEEK coatings. [34] In the case of electrophoretic deposition of PEEKbased coatings reinforced with Si 3 N 4 amorphous particles (size up to 50 nm) problems were encountered in obtaining homogeneous coatings on the Ti-13Nb-13Zr titanium alloy. Introduction of the cationic polyelectrolytes polyethylenimine and chitosan into an EtOHbased suspension facilitated the deposition of coatings.…”