Fabrication of Boronized Ti6Al4V/HA Composites by Microwave Sintering in Mixed Gases

Abstract

The effect of atmosphere on the fabrication of boronized Ti6Al4V/hydroxyapatite (HA) composites was investigated by microwave sintering of the mixture of Ti6Al4V alloy, HA, and TiB 2 powders at 1050 °C for 30 min in the mixed gases of Ar + N 2 , Ar + CO, and Ar + H 2 , respectively. The presence of N 2 , CO, and H 2 in the atmosphere caused formations of TiN, TiC, and TiH 2 in the composites, respectively, together with evident microstructural changes that determined the mechanical properties (compressive strength, compressive modulus, and Vickers microhardness) and wettabilities of the composites after sintering. It was found that the composite exhibited the best mechanical performance with compressive strength of 148.59 MPa, compressive modulus of 13.9 GPa, and Vickers microhardness of 300.39 HV by microwave sintering in the mixed gas of Ar + H 2 , followed by those obtained in the mixed gases of Ar + N 2 and Ar + CO. All of the composites possessed desirable wettabilities, irrespective of the sintering atmosphere, as demonstrated by their very low water contact angles (≤31.9°). The results indicated that it is critical to control the extents of nitration and carbonization for maintaining the performance of the composites, especially the mechanical properties, whereas there is no strict requirement for the same objective using the mixed gas of Ar + H 2 in which qualified composites could be obtained for implant applications.

Fabrication of Hydroxyapatite/Tantalum Composites by Pressureless Sintering in Different Atmosphere

“…In general, vacuum sintering and atmosphere sintering (typically Ar atmosphere) are used to prevent adverse reactions between different components. For example, the sintering of HA/Ti composites is usually carried out in an argon atmosphere to prevent the oxidation of Ti. − Moreover, sintering atmosphere has been proved to have a great influence on the properties of the composites. , Obviously, it is essential to evaluate the effect of atmosphere on the sintering process of HA/Ta composites, which has not yet been reported systematically.…”

“…12−14 Moreover, sintering atmosphere has been proved to have a great influence on the properties of the composites. 15,16 Obviously, it is essential to evaluate the effect of atmosphere on the sintering process of HA/Ta composites, which has not yet been reported systematically. The present investigation is an attempt to investigate the influences of sintering atmospheres and temperatures on the properties of HA/Ta ceramic composites.…”

Microwave-assisted synthesis of composites based on titanium and hydroxyapatite for dental implantation

“…It was reported that the boronized Ti6Al4V/HA composite could be prepared by microwave sintering at 1050 °C for 30 min under an Ar atmosphere using Ti6Al4V powder of 15-50 μm, TiB 2 powder of 4-8 μm, and needle-like HA with a diameter less than 20 μm and a length less than 100 μm as raw materials. 12,60,72 Its micromorphology is shown in Fig. 7D.…”

“…Many studies have confirmed that microwave heating could achieve better performance than conventional heating in materials synthesis and processing. [12][13][14][15] Microwave energy is characterized by the volumetric thermal effect due to its large wavelength, which allows the energy to be absorbed in a large material volume (Fig. 1).…”

“…However, there are rare reviews on the preparation of composites based on Ti and HA by microwave coating or sintering for dental implantation. 12 The aim of this study was to provide a detailed review of microwave-assisted synthesis of composites based on Ti and HA for dental implantation. Because of its similarity to Ti, the most popular titanium alloy, Ti6Al4V, was also considered.…”