An experimental method was developed to determine the through thickness elastic modulus profile of a multi-layered functionally graded material. The method consists of two sets of mechanical experiments, a tensile test and a four-point bend test, from which the strains at two locations on either surfaces of the beam are measured for known applied loads. A one-dimensional version of classical laminate theory is then used to calculate the beam stiffness coefficients from the experimentally obtained data. Finally, an inverse analysis is performed in which a minimization scheme using Genetic Algorithm is utilized to determine the elastic modulus of each layer. The applicability of such method is demonstrated for a seven-layered ceramic/metal functionally graded structure with layers ranging from pure Ti to 85 % TiB-15 % Ti on the ceramic-rich side. The elastic modulus of each layer within the examined material is back calculated based on the proposed inverse analysis. The results indicate that the proposed method can be used to obtain the through thickness elastic modulus profile of discretely graded materials with reasonable accuracy.
All Science Journal Classification (ASJC) codes
- Aerospace Engineering
- Mechanics of Materials
- Mechanical Engineering