In the present paper, mechanical properties of the carbon-nano-fiber reinforced plastic are discussed. Two kinds of carbon-nano-fiber are employed for the filler of the composites, which are vapor grown carbon fiber (VGCF) and cupsstacked carbon nanofiber (CNF(CS)). For the matrix of the composites, four kinds of thermoplastic resin are used which are polypropylene (PP), polyamide (PA12) poly-buthylene-terephthalate (PBT) and poly-ether-ether-ketone (PEEK). 3-point bending test using short beams are executed to obtain the anisotropic properties of the specimens processed by injection molding. Standard tensile tests are executed to evaluate the stress-strain relation, tensile strength and elastic moduli of the composite materials. Furthermore, Mode I fracture toughness of the composite are evaluated using center-notched flexure specimens. These mechanical properties and characteristics for the specimens are compared and discussed in detail, and the mechanism of the fracture are investigated by scanning electron microscope (SEM).

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In the present paper, numerical simulation about press forming process of glass lens using finite element method is demonstrated. Generally, material properties of glass, e.g. viscoelastic constants and coefficient of thermal expansion, depend on time-history and temperature. In the present study, creep test has been conducted to determine the thermoviscoelastic properties of glass. The creep function obtained by the actual measurement has been transformed into relaxation function employing Laplace transform and its inversion. Shift factor which gives the relation between the time and temperature can be determined by creep test, too. Some numerical simulation by FEM are executed to obtain the residual stress and residual deformation under several thermal conditions changing the cooling time, and the optimal condition during forming process of glass lens is discussed in detail.

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The result from applied the enriched finite element on shear load model is agreed with using FEM. However, the results from changing the size of enriched element effects the stress intensity factors varied from FEM results. This is an important point for continue study. In additional, on this time we have considered only shear stress loading. The next step is to combine both shear and normal stress singularities on the model under shear load.

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