Effect of Yttria on the Phase Formation and Sintering of HA-Al₂O₃Biocomposites

Abstract

Hydroxyapatite is very-well known as the main component of hard tissues and, as such, it has attracted much attention by researchers in the recent decades. This study was aimed to present the characterization of Y2O3 doped 50 wt.% hydroxyapatite -50 wt.% Al2O3 composite materials fabricated at relatively high temperature of 1600• C. Hydroxyapatite powder was obtained from bovine bones via calcination and ball milling technique. Fine powders (≤ 1 µm) of hydroxyapatite/Al2O3 were admixed with 0.5 and 1 wt.% Y2O3 powders. Powder compacts were sintered at 1600• C for 4 h in air atmosphere. The field emission scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction studies following the relative density measurements were conducted. Moreover, the microhardness was studied as the mechanical property of sintered samples. The effect of increasing Y2O3 content on surface morphology, elemental distribution and phase evaluation was investigated in hydroxyapatite/Al2O3 biocomposite materials. It was found that by increasing Y2O3 content, the relative density increased up to 98.8%, while the hardness increased to 863 HV (0.2) . The main phases, which were found, are Hibonite -CaO(Al2O3)6 and beta-tricalcium phosphate -Ca3(PO4)2, according to X-ray diffraction pattern.

Sert Doku Uygulamaları İçin Makro Gözenekli Alüminyum Oksit-Bor Karbür Seramikleri

“…Although Al2O3 is highly biocompatible and wear-resistant, it possesses low flexural strength and toughness (Marti, 2000). In order to enhance its mechanical properties, two composite materials have been developed by incorporating a second phase (Jang et al, 1995;Öksüz and Özer, 2017) or embedding whisker (Tan et al, 2020) into an Al2O3 matrix.…”

The effect of yttrium oxide in hydroxyapatite/aluminum oxide hybrid biocomposite materials: Phase, mechanical and morphological evaluation

“…Extensive studies have indicated that hydroxyapatite is biocompatible with hard tissues of human beings and exhibits osteoconductive properties [3]. Thus, it is considered as the most promising bioactive material for clinical use [4][5][6]. However, despite its good biocompatibility and bioactivity, the low mechanical strength of hydroxyapatite restricts its applications for small and low load bearing implants and/or surface-coating of different im-plant materials [7][8].…”