Drill Shaft Orientation
An engineer just thought of a new idea for a drilling shaft where the shaft
is made from two different materials. His boss is not so sure of the idea and
demands a stress analysis before any prototype is constructed.
What is known:
- The drill shaft is constructed from two materials, steel and aluminum.
- The drill motor will deliver a torque of 15 kip-ft. It is assumed
that there is no friction along the length of the shaft.
- The outside section is made from steel and has an outside diameter of 4
in and an inside diameter of 3.5 in.
- The inside section is made from aluminum and has an outside diameter of
3.5 in and an inside diameter of 3.0 in.
- The two sections are rigidly attached (no slipping between the two materials).
- The aluminum material properties are EA = 10,000 ksi and νA =
- The steel material properties are ES = 29,000 ksi and νS =