A composite has 40 % Vf of a 150 µm diameter fiber. The fiber strength is 2 GPa, the matrix strength is 75 MPa, while the fiber/matrix interfacial strength is 50 MPa. Assuming a linear build up of stress from the two ends of a fiber, estimate the composite strength for (a) 200 mm long fibers and (b) 3 mm long fibers.

5. The following table shows data from a flow study of a PS melt at 210°C in a capillary rheometer. a. Make a plot of log shear stress versus log shear rate. b. Calculate the value of the viscosity at 1 and 135 s', respectively. Shear Stress ,(10° dyn/cm') Shear Rate, 3.5 1.0 12.0 5.0 20.0 12.2 33.0 25.0 40.0 52.5 60.0 135.0 69.8 400.0

Produce a plot (graph) showing the shape of the PVT-surface for the ideal gas equation.

Question: A cylindrical rod of 1040 steel originally 11.4 mm (0.45 in.) in diameter is to be cold worked by drawing;  the circular cross section will be maintained during deformation.  A cold-worked tensile strength in excess of 825 MPa (120,000 psi) and a ductility of at least 12%EL are desired.  Furthermore, the final diameter must be 8.9 mm (0.35 in.).  Explain how this may be accomplished.

4. Polyethylene (HDPE) pipe is used as a strut in a crutch 22 mm assembly. The pipe generally prepared by extrusion followed by external cooling. The attached figure is a plot of variation of density through a PE pipe. a.) What is the % 958- 956 954 1952 bore pipe wall Outside Density (kg m 3)

5. The resistance of a material to force which is tending to deform or fail by crushing. a. Parent metal b. Physical property c. Compressive strength d. Elongation