Answer Happy

4) For each of the statements of following questions, one or more of the completions given are correct. Choose the correct completions. a) The Young's modulus of an aligned continuous fibre metal matrix composite 1. Increases with increasing volume fraction of fibre, 2. Is independent of volume fraction of fibre 3. Is the same in the longitudinal and transverse direction, 4. Is greater in the longitudinal direction, 5. Is greater in the transverse direction. b) The transverse tensile strength of an aligned continuous fibre composite 1. Is obtained when testing normal to the fibre axis, 2. Is obtained when testing parallel to the fibre axis 3. Is lowest tensile strength 4. Is the highest tensile strength 5. Depends mainly on the properties of the matrix and of the fibre matrix interface 6. Depends mainly on the properties of the fibre.

3) Tensile tests are applied on two type of fibers SiC and Al2O3, their densities are respectively 3.3 Mg/m³ and 2.6 Mg/m³. The deformation was elastic up to the failure of the fibers. The average tensile strength and strains to failure were: 1500 MPa and 0.4% for alumina fibers and 2200 MPa and 1% for SiC fibers. Calculate the specific modulus and specific strength for these two fibers.