(a) A bar specimen having a square cross section of edge length c is subjected to a uniaxial tensile force F, as shown in the fol- lowing figure. Derive strength and stiffness performance index expressions analogous to Equations 22.9 and 22.11 for this bar. Analysis and that in part b, which alloy would you select on a stiffness-per-mass basis?
(d) Now select those metal alloys having strength performance indices greater than 120 (for sy and r in units of MPa and g/cm3, respectively), and rank them from highest to lowest P.
(e) And, using the cost database, rank the materials in part d from least to most costly. Relative to this analysis and that in part d, which alloy would you select on a strength-per-mass basis?
(f) Which material would you select if both stiffness and strength are to be con- sidered relative to this application? Justify your choice.