The research was carried out in association with University of Malaya, Malaysia, and Gadjah Mada University, Indonesia.
The aim of the research was to investigate the production method of a type of hydroxyapatite that is compatible with human body and has desirable mechanical properties such as higher strength and higher resistance against abrasion and scratch. During the investigation of the desired properties, nano-identation and nano-scratch tests were successfully carried out on hydroxyapatite samples.
Dr. Majid Reza Ayatollahi, the supervisor of the research, explained why these tests had been chosen. "There is no need for large samples to carry out nano-identation or nano-scratch tests. Therefore, they are very good for biological materials that are relatively expensive. On the other hand, the tests can be repeated on a sample due to their non-destructive nature. The possibility to precisely control the charge and the diffusion of the identator and the lack of the presence of chemical or electrical fields are among the advantages of the test."
According to the results, the maximum amount of Young's Module for hydroxyapatite is obtained at sintering temperature of 1200°C while the minimum value is reached at 1000°C. The increase in the sintering temperature from 1000°C to 1300°C increases the toughness of hydroxyapatite. More increase in the sintering temperature has negative effect on the toughness. At all sintering temperatures, the amount of toughness obtained from nano-scratch test was higher than that obtained from nano-identation test.