Engineering 151 Test Module 7 Through 9

1)

 

A steel cable 1.25 inches in diameter and 50 ft long is to lift a 40,000 lb weight. What is the length of the cable during lifting? The modulus of elasticity of the steel is 30×10⁶ psi.

 

2)

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.

 

3)

 

 

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