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Mechanical behavior of live cells and tissues is non-linear and their deformations are large. Using a suitable mechanical model that could predicts this behavior, is an important step in the prevention and treatment of various diseases and the production of artificial tissues. In this paper, using the non-linear elasticity theory and non-linear Mooney-Rivlin model, mechanical analysis of human arteries has been studied under internal pressure and axial tension. In the first By using the experimental study was conducted of biaxial test, the elastic constants of the arteries are calculated. For modeling, the arteries are considered as long homogeneous and isotropic cylinders. Radial and circumferential stress distribution on the minimum and maximum blood pressure is calculated. Variation of artery radius due to internal pressure is calculated and compared with the reported experimental data, and a good agreement is seen. The stress distribution curves versus radius are plotted which show that the inner layers of the arteries have much greater role in stress distribution than the outer layers. The elastic constants which are calculated for different ages show that the arteries of older people become stiffer and their flexibility decrease.

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With the emergence and expansion of additive manufacturing processes, especially the fused deposition modeling process, extensive research has been conducted on these processes. One important research area is strengthening the printed parts by the fused deposition modeling method. One of the main areas of research is related to the strengthening of printed parts by the fused deposition modeling method. This process enables the production of complex structures and the customization of parts. On the other hand, polylactic acid material is one of the main materials used in this process, which has been noticed over other materials due to its biocompatibility and biodegradability properties. In this research, the effect of annealing heat treatment on the compressive strength and modulus of porous samples has been investigated with the approach of using them in tissue engineering as a scaffold for bone tissue. The samples are 3D printed with wiggle, grid, and honeycomb patterns and with filling percentages of 40, 70, and maximum. In addition, the effect of two parameters, the extrusion width, and the layer height, has also been investigated. To create porous structures with interconnected porosities, the pattern of filling in each layer is rotated to a certain extent, and this causes the introduction of new porous structures that can have wide applications such as being used as scaffolds in tissue engineering. After evaluating the compressive mechanical properties of the samples, the same samples were heat treated, and then their compressive mechanical properties were also evaluated. The obtained results show that the maximum compressive strength and modulus occur in the sample with an extrusion width of 0.6 mm, layer height of 0.25 mm, wiggle filling pattern, and maximum filling percentage. The values ​​of compressive strength and modulus for the non-heat-treated sample are equal to 84.51 MPa and 2.28 GPa respectively and for the heat-treated sample, it is equal to 105.44 MPa and 2.29 GPa respectively.