Synthesis and characterization of stabilized zirconia toughened alumina (ZTA) doped niobium pentoxide (Nb₂O₅)

Abstract

The main target of this research is to study the mechanical properties of the Nb₂O₅ doped with alumina-zirconia composites. Pellets form samples of ZTA (5YSZ) doped niobium pentoxide in varied amount of 0%, 0.3%, 0.5% and 0.7% were prepared by solid-state conventional method with respective 4:1 ratio (alumina and zirconia). Effect of dopant addition at different amount was studied on the morphology, phase transformation and hardness of the ceramics samples. Each of the compositions were calcined at 1000°C followed with pellets production by pressing at 220 MPa and then they were sintered at 1650°C with heating rate 10°C min-1 and holding for 2 hours in air. Phase trasnformation, phase quantification and crystal structure analysis was revealed by using X-ray diffraction data (XRD) with the help of X-Pert HighScore Plus software using Rietveld Refinement Method. The hardness of the composite is determined by using Vickers hardness test while microstructure was observed by scanning electron microscopy (SEM). It was found that addition of niobium pentoxide (Nb₂O₅) up to 5wt% had a positive effect on the microstructure and hardness of the ZTA ceramics sample. This mean that improvement from 1759.8 HV (ZTA) to 1828.62 HV (ZTA0.5) which mean 3.91% improvement compared to undoped sample.