Papers by Author: Taik Nam Kim

Abstract: Molten Soda lime glass (SLG) was penetrated into the surface of ZTA at 1500°C for the holding time of 1 to 10 h. The depth of the glass penetration increased with increasing holding time. The thermal expansion mismatch and elastic property mismatch between the penetrated glass and ZTA produced residual compression in the surface region during cooling. This residual compression enhanced the flexural strength and fracture toughness remarkably.

Abstract: In the present work, surface treatment of surgical implant Titanium alloy with micro bioactive nanotube was experimented. Surface treatment of Ti-6Al-4V bio-implant carried out by giving alkali hydrothermal and heat treatment. The specimens were treated in 1M NaOH at 100, 150, 200°C for different holding time of 2 hr, 4 hr, 6hr, 12 hr, 24hr & 48 hr. The hydrogel layer generated during the alkali treatment was crystallized to sodium titanate (Na2Ti6O13) and resulted into the formation of nano sized tubes on heat treatment. X-ray Diffractrometry (XRD), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) revealed the different phases and surface morphology of these nanorods. The biocompatibility test done using Simulate Body Fluid (SBF) showed that the Hydroxyapatite (HAp) was well formed at the sodium titanate nanotube layer generated on the Ti-6Al-4V specimen. The best condition for this increase in surface biocompatibility was optimized to 6 hours hydrothermal treatment under 200°C using 1 M NaOH followed by 1 hour heat treatment at 600°C.

Abstract: In this study hydroxyapatite (HA) was coated by sol-gel method on Ti6Al4V alloy substrates: on micropolished surface and after titania (titanium oxide) treatment. Former shows the cracks and poor bonding of HA whereas latter shows coating without cracks and higher bonding strength. The higher bonding strength of HA coating in titania treated sample could be attributed to the increased roughness by titanium oxide layer.