Microstructure and mechanical properties of porous Ti-6Al-4V composites with bioceramics fabricated by spark plasma sintering
Agata Dudek, Magdalena Klimas
Quarterly No. 1, 2014 pages 23-28
DOI:
keywords: SPS method, metallic-ceramic composites, hydroxyapatite, zirconia, alumina
abstract Substantial progress in the field of materials used for medicine has be observed in recent years, driven by the higher demand for these types of materials. Promising prospects are offered by composite materials that allow for unlimited modelling of the properties in materials used for specific medical applications. The focus of the investigations presented in this paper is placed on metallic-ceramic composites based on a titanium alloy matrix (Ti-6Al-4V) with a 20 wt.% addition of aluminium oxide (Al2O3), hydroxyapatite ceramics (Ca10(PO4)6(OH)2) and YSZ (zirconia stabilized with 8 wt.% yttria Y2O3) obtained using the spark plasma sintering method. The specimens were compressed at 35 MPa and sintered in a shielding gas (argon) medium at the temperature of 1000°C in an SPS HP 5 apparatus manufactured by FCT for 25 min. The obtained composites were subjected to microstructural analysis using an Axiovert light microscope and X-ray quality analysis using a D8 DISCOVER Bruker diffractometer. Hydrostatic weighing in deionized water according to the PN EN ISO 2738: 2001 standard was also used to evaluate the density (apparent and relative), porosity (open and total) and water absorption capacity. The topology of the surface of the metallic-ceramic composites was determined using a Hommel T1000 profilometer. The mechanical properties (microhardness) were measured using a semi-automatic microhardness tester (FM-7, FutureTech) with a Vickers indenter at a load of 100 G. The resistance to wear was evaluated by means of a ball wear testing stand. In this study, Ti6Al4V/HAp(ZrO2, Al2O3) composites were prepared using spark plasma sintering (SPS) to obtain highly compact composites. The aim of the study was to evaluate the ability of spark plasma sintering to obtain metallic-ceramic composites based on titanium alloy with an addition of inert ceramics and bioactive ceramics for medical applications.