Structural and morphological analysis of zinc incorporated non-stoichiometric hydroxyapatite nano powders

In this study, Zn incorporated non-stoichiometric hydroxyapatite (nHAp) was synthesized via precipitation method and effect of the incorporation of Zn (fraction: 2, 4, 6 and 8 mol-%) on the microstructure of nHAp was studied by XRD, FTIR analysis and SEM-EDS techniques. The formation of nHAp was confirmed by XRD and FTIR those showed that no secondary phase was formed through the Zn incorporation. The SEM studies also revealed that particles were formed in nano-metric size (30-60 nm). It was found that crystallite and particle size of Zn incorporated nHAp gradually decreased up to 6 mol-%, and started to increase while the Zn fraction reached up to the 8 mol-% and hence the morphology of the aggregated products was also changed. It can be concluded that the incorporation of Zn cations cause to form nHAp phase. Furthermore, the nHAp microstructure has deviated from stoichiometric condition by incorporation of more Zn cations.Keywords: Microstructure; Nanopowder; Non-Stoichiometric Hydroxyapatite; Zn Incorporatio

Structural and morphological analysis of zinc incorporated non-stoichiometric hydroxyapatite nano powders

ABSTRACT In this study, Zn incorporated non-stoichiometric hydroxyapatite (nHAp) was synthesized via precipitation method and effect of the incorporation of Zn (fraction: 2, 4, 6 and 8 mol-%) on the microstructure of nHAp was studied by XRD, FTIR analysis and SEM-EDS techniques. The formation of nHAp was confirmed by XRD and FTIR those showed that no secondary phase was formed through the Zn incorporation. The SEM studies also revealed that particles were formed in nano-metric size (30-60 nm). It was found that crystallite and particle size of Zn incorporated nHAp gradually decreased up to 6 mol-%, and started to increase while the Zn fraction reached up to the 8 mol-% and hence the morphology of the aggregated products was also changed. It can be concluded that the incorporation of Zn cations cause to form nHAp phase. Furthermore, the nHAp microstructure has deviated from stoichiometric condition by incorporation of more Zn cations

Role of Ti3AlC2 MAX Phase on Characteristics of In-situ Synthesized TiAl Intermetallics. Part III: Microstructure

In this paper, the 3rd part of a series of publications on the sinterability and characteristics of TiAl–Ti3AlC2 composites, the microstructure development during the synthesis and sintering processes was studied by scanning electron microscopy (SEM). Chemical evaluation of various phases in the developed microstructures was performed using energy-dispersive X-ray spectroscopy (EDS) in different ways such as point, line scan and two-dimensional elemental map analyses. For this purpose, five samples were fabricated with different percentages of Ti3AlC2 MAX phase additive (10, 15, 20, 25 and 30 wt%). Ball-milling and spark plasma sintering (SPS: 900 °C/7 min/40 MPa) of as-purchased Al and Ti powders with already-synthesized Ti3AlC2 additive were selected as composite making methodology. SEM/EDS analyses verified the in-situ manufacturing of TiAl/Ti3Al intermetallics as the matrix during the SPS process and the presence of Ti3AlC2 as the ex-situ added secondary phase. Moreover, the in-situ synthesis of Ti2AlC, another member of MAX phases in Ti-Al-C system, was also detected in titanium aluminide grain boundaries and attributed to a chemical reaction between TiC (an impurity in the initial Ti3AlC2 additive) and TiAl components

Role of Ti3AlC2 MAX Phase on Characteristics of In-situ Synthesized TiAl Intermetallics. Part II: Phase Evolution

In this research, the 2nd part of a series of papers on the processing and characterization of TiAl–Ti3AlC2 composites, the phase evolution during the manufacturing process was investigated by X-ray diffraction (XRD) analysis and Rietveld refinement method. Metallic Ti and Al powders with different amounts of previously-synthesized Ti3AlC2 additives (10, 15, 20, 25 and 30 wt%) were ball-milled and densified by spark plasma sintering (SPS) under 40 MPa for 7 min at 900 °C. Before the sintering process, XRD test verified that the powder mixtures contained metallic Ti and Al as well as Ti3AlC2 and TiC (lateral phase synthesized with Ti3AlC2) phases. In the sintered composites, the in-situ synthesis of TiAl and Ti3Al intermetallics as well as the presence of Ti3AlC2 and the formation and Ti2AlC MAX phases were disclosed. The weight percentage of each phase in the final composition of the samples and the crystallite size of different phases were calculated by the Rietveld refinement method based on the XRD patterns. The size of Ti3AlC2 crystallites in sintered samples was compared with the crystallite size of synthesized Ti3AlC2 powder