Öztürk, Suat | Yetmez, Mehmet
Article | 2016 | Advances in Materials Science and Engineering2016
Sintering effects and mechanical properties of bovine hydroxyapatite/CaTiO3 composites are investigated for different CaTiO3 ratios. Results indicate that densities of the biocomposites increase while total porosities of those decrease with increasing sintering temperature. Moreover, modulus of elasticity and microhardness increase with increasing sintering temperature. However, values of both toughness and fracture toughness of the biocomposites generally rise with increasing sintering temperature except for 1300°C. © 2016 Suat Ozturk and Mehmet Yetmez.
Yetmez, Mehmet
Article | 2014 | Advances in Materials Science and Engineering2014
The sintering behavior and the mechanical properties of a mechanical mixture of hydroxyapatite and tricalcium phosphate (BCP) ceramics with the composition of 30% HA and 70% TCP are experimentally investigated in the temperature range between 1000°C and 1300°C. The results show that consolidation, grain growth, and Vickers hardness generally increase with increasing sintering temperature up to 1200°C. However, microstructure observation indicates that cracks are formed along the grain boundaries as well as in the bulk of the grains after sintering at 1200°C. Moreover, the best values of compressive strength, modulus of elasticity, a . . .nd toughness are achieved in the samples sintered at 1100°C. These properties at 1100°C decay with sintering at 1200°C and increase again after sintering at 1300°C. © 2014 Mehmet Yetmez Daha fazlası Daha az
Özkalaycı, Nurhat | Yetmez, Mehmet
Article | 2016 | Advances in Materials Science and Engineering2016
The aim of this study is to present a new appliance called stability leg designed as an additional anchorage providing device for increasing primary stability of orthodontic miniscrew. For this purpose, two finite element models (FEMs) with two different cortical layer thicknesses of 1 mm and 2 mm are considered. In order to achieve the stability analysis, these two main models, namely, Model I and Model II, are divided into subgroups according to stability leg lengths. Two types of forces are considered. (1) First force is a constant force of 1 N which is applied to all two models. (2) Second force is defined in the range of 1-4 N. . . . Each of 1, 2.5, and 4 N of the second force is applied with a position angle ranging from 34° to 44°. Results show that stability of a miniscrew with 5 mm leg increases primary stability of the miniscrew. © 2016 Nurhat Ozkalayci and Mehmet Yetmez Daha fazlası Daha az