Papers by Author: N. R. Ha

Paper TitlePage

Authors: N. R. Ha, Z. X. Yang, Kyu Hong Hwang, J. K. Lee
Abstract: Pure Titanium alloys are superiorities of biocompatibility, mechanical properties and chemical stability. The biocompatibility of Ti alloy is related to the surface effect. In this study, Ti Alloys were treated by alkali and acid activation process. And through the sol coating layer, biocompatibility were investigated. Consequently, it appeared that the porous layer was generated on the surface of alloy by surface treatment and sol coating process. It was found that with surface treatment on Ti alloy, the formation speed of porous was much quicker compared with those ones without treatment. Therefore, the biocompatibility was improved.
Authors: Z. X. Yang, N. R. Ha, M.S. Jang, Kyu Hong Hwang
Abstract: As a relatively new material, geopolymer concrete offers the benefits as a construction material for sustainable development. It utilized waste materials such as recycled concrete sludge, fly ash and etc. It has a very low rate of green house gas emission when compared to ordinary Portland cement. In this study, the component of geopolymer is concrete sludge, metakaolin and water glass, NaOH was used as alkalin activator. To improve the mechanical properties, the amount of NaOH and water glass were varied to obtain higher strength and the specimens were cured both in air and water, then their mechanical properties like compressive strength and bending strength were measured the microstructures were investigated.
Showing 1 to 2 of 2 Paper Titles