The mechanical properties of biomedical materials were determined and discussed in this study. The extension and tensile tests for aorta and coronary artery were carried out using tensile testing machine. Based on incompressibility of biological soft tissue, the stress-stretch curves of arteries were obtained. This study proposed a nonlinear Ogden material model for the numerical simulation of coronary artery extension during stent implantation. The corresponding Ogden model parameters were derived by the obtained stress-stretch curves from tensile tests. For validation, the proposed nonlinear Ogden material model for coronary artery was applied to a Palmaz type stent implantation process. The simulated stent deformation was found to be reasonable. It had a good correlation with the measured results.
The microindentation experiments were used to measure the mechanical properties of enamel and dentine of human teeth in this study. To reveal the relation between the experimental parameters and measured mechanical properties, Young¡¦s moduli were investigated by varying experimental parameters. The parameter of maximum indentation load significantly influences measured values. Young¡¦s modulus varies very slightly when 10 to 100 mN of maximum indentation load applied. Young¡¦s modulus is not sensitive to the parameters of portion of unloading data and teeth age.
The combination of finite element analysis and curve-fitting method is proposed to determine the mechanical properties of thin film deposited on substrate. The mechanical properties of thin film, i.e. Young¡¦s modulus, yield strength and strain-hardening exponent, were extracted by applying an iterative curve-fitting scheme to the experimental and simulated force-indentation depth curves during the microindentation loading and unloading processes. The variation of mechanical properties of TiN thin films with thicknesses ranging from 0.2 to 1.4 £gm was extracted. The results presented the film thickness effect makes the Young¡¦s modulus of TiN thin films reduces with reducing film thickness, particularly at thicknesses less than 0.8 £gm. Therefore, it can be inferred that a film thickness of 0.8 £gm possibly represents the upper bound when employing macroscopic mechanics with bulk material properties.
Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0829112-142316 |
Date | 29 August 2012 |
Creators | Chien, Hui-Lung |
Contributors | Shyh-Chour Huang, Bo-Wun Huang, Chi-Hui Chien, Yung-Chuan Chen, Der-Min Tsay, Ming-Hwa Jen, Ying-Chien Tsai, Jao-Hwa Kuang |
Publisher | NSYSU |
Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
Language | Cholon |
Detected Language | English |
Type | text |
Format | application/pdf |
Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0829112-142316 |
Rights | user_define, Copyright information available at source archive |
Page generated in 0.0012 seconds