A large flat plate is subjected to constant amplitude uniaxial cyclic tensile and compressive stresses. Compute the critical crack length if the fatigue life must be at least 3×106 cycles. Assume the initial maximum edge surface crack length to be 1.1 mm, and a maximum tensile stress of 160 MPa. Assume m=3.0, A=1.4×10-13MPa in meter units, and Y=1.2.
Using the attached figure, for a Cu-20% Wt Ag alloy, determine the phases present, their percentage amounts, and their compositions at
a. 1000 degrees Centigrade
b. 781 degrees Centigrade
c. 779 degrees Centigrade