MECHANICAL PROPERTIES AND MICROSTRUCTURAL BEHAVIOR OF HYDROXYAPATITE/TIO2 ELECTROSPUN NANOFIBERS CONSOLIDATED USING HIGH FREQUENCY INDUCTION HEAT SINTERING

Abdelrazek Khalil, Khalil

doi:10.21608/jesaun.2007.114598

MECHANICAL PROPERTIES AND MICROSTRUCTURAL BEHAVIOR OF HYDROXYAPATITE/TIO2 ELECTROSPUN NANOFIBERS CONSOLIDATED USING HIGH FREQUENCY INDUCTION HEAT SINTERING

Document Type : Research Paper

Author

Khalil Abdelrazek Khalil

Permanent: Aswan High Institute of Energy, South Valley University, Aswan, Egypt Currently: Division of Advanced Materials Engineering, RCIT, Chonbuk National University, Jeonju 561-756, South Korea

10.21608/jesaun.2007.114598

Abstract

In order to improve fracture toughness of hydroxyapatite (HAp), TiO2 electrospun nanofibers were used as reinforcement. TiO2 nanofibers with diameters of 50–400 nm were first prepared by calcining and presintering of electrospun nanofibers of polyvinyl acetate (PVac)/Titania composite at different temperatures. The composite of HAp with 5 wt % of electrospun TiO2 nanofibers were then sintered by high frequency induction heat sintering technique. Mechanical properties were evaluated by three-point bending tests, indentation tests and compression test. The results indicated that the morphology and crystalline phase of TiO2 nanofibers were strongly influenced by the calcination temperature. Additionally, the SEM results showed that the nanofibers calcined at 600  C are porous structure due to the low densification. There was a significant change of microstructure with increasing calcination temperature to 800  C. The nanofibers were appeared with dense microstructure due to the high temperature calcination. A number of large size particles or particle aggregates connected by a small neck were found after the nanofibers were calcined at 1000 ◦C. The sintering behaviors, toughness and hardness of the resulting composites were significantly affected by the calcinations temperature of the included TiO2 nanofibers. The bending and compressive strength values of HAp/5 wt. % TiO2 composites sintered at 1050  C were 119 and 120 MPa respectively, when the calcination temperature of the TiO2 nanofiber was 800  C, while the strength is decreased with decreasing or increasing calcination temperature than 800  C.

Keywords