a. Name and draw out the three common crystal structures of metals (Hint: suggest the use of small circles to represent atom centers) identify the following metals with each of these structures (iron at room temperature, aluminum, copper, zinc).

b. Calculate the number of atoms in a BCC unit cell and an FCC unit cell (show all working).

c. A ferrous alloy component will be subject to high cyclic loading in service. What potential failure mechanism should be considered? Sketch a graph showing a typical failure under these conditions. How can the lifetime be increased or chances of failure reduced? Is there a safe stress for a ferrous material under these conditions. Would this be the case if the alloy were replaced by an Al alloy? If not explain why.