# Material Science

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1. You are specifying materials for a design; the design calls out for the use of steel tube. The tubes will be in a state of tension with a load of 15,000 lbf. Your analysis is done using 1018 hot-rolled steel. The tubes are 2" O.D, with a wall thickness of 0.32".

A) Determine and State the resulting stress, is this a suitable material selection for the load given.
B) If the tube is 3 feet long and subjected to the load given, what will be the final outside diameter?
C) If the tube was then pulled with a true stress equal to 53,000 psi, determine the final length of the 3 ft tube after this higher load is relaxed (removed).

2. A nickel coating is being plated to a 316L Stainless steel frame for use in a power plant. During the heat treatment process a nickel powder is packed around the frame with a concentration level of 75% nickel. After 168 hours in the heat treatment process, the nickel coating is determined to be 25 wt % Ni at a depth of .75 mm. Determine the temperature at which this process was performed?

3. Calculate and show
A) the APF for Chromium (show all work, don't just write down the APF number)
B) the planer density for the chromium slip system {110}<111>
C) the linear density for the chromium slip system {110}<111>

4. You are cold drawing a brass piece to obtain a final diameter of a round bar to 6 mm. The final strength and ductility are as specified: yield strength >= 325 MPa, ductility %EL >= 20%.
A) Determine the pre-deformed diameter using the average of the allowable range of %C. W. (percent cold worked), and state this average value.
B) Estimate the hardness of the finished bar stock
C) Determine the diameter of the expected BHN impression, using an effective load of 3000 kg.