Explain what is meant by ‘materials science’. Explain in less than 150 words.
You would like to design a racing bicycle frame for Cadel Evans, the winner of the 2011 Tour de France, for the race next year.
What types of material properties would you recommend? What materials
might be appropriate? Explain in less than 200 words.
A steel cable with a diameter of 25 mm and 50 meters long is to lift a 20 ton (20,000 kg) load. What is the length of the cable during lifting? (Assume the Young’s modulus of steel is 210 GPa).
The following three ????data points are provided for a titanium alloy for a biomedical hip joint:
???????????????= 0.002778 (at ??= 300 MPa)
???????????????= 0.005556 (at ??= 600 MPa)
???????????????= 0.009897 (at ??= 900 MPa)
Calculate the Young’s modulus (E) for this alloy.
The strength of titanium alloy is found to be 450 MPa when the grain size is 17 x 10-6 m and 565 MPa when the grain size is 0.8 x 10-6 m. Determine:
(a) the constants in the Hall-Petch equation and
(b) the strength of the titanium alloy when the grain size is reduced to
0.2 x 10-6 m.
Explain the difference between a “single crystal” material and a “polycrystalline” material. Explain in less than 100 words.
A university campus has 200 classrooms and 400 faculty offices. The classrooms are equipped with 12 fluorescent tubes, each consuming 110 W, including the electricity used by the ballasts. The faculty offices, on average, have half as many tubes. The campus is open 240 days a year. The classrooms and faculty offices are not occupied an average of 4hours a day but the lights are kept on. The unit cost of electricity is $0.082/kWh, determine how much the campus will save a year if the lights in the classrooms and faculty offices are turned off during unoccupied periods.