Download Practice Exam 1 Questions for Fundamentals of Materials | ENGR 220 and more Exams Materials science in PDF only on Docsity! Grades: #1__________ #2____________ #3____________ #4_________ Total____________ ENGR 220 PRACTICE EXAM I: FALL 2009 Name Student Number Section Number_____________ Closed book, closed note exam. Formulas given on attached formula sheet. You may use a calculator, periodic table and ruler. You will be given one hour to complete the exam. Please show all work for full credit. 1. 1 .(30 pts, 3 pts each) Please respond True or False to the statements listed below. RECORD YOUR ANSWERS ON THE SPACES GIVEN AT THE BOTTOM OF PAGES ONE AND TWO. WRITE OUT ENTIRE WORD: TRUE OR FALSE a. You are given two material samples. The first has a very fine grain or crystal structure (a lot of small crystals) while the second has a courser grain structure (larger crystals). The processing conditions of the two materials were likely the same. b. Propane (C3H8) has a higher melt temperature than dodecane (C12H26). c. The higher the bond energy for an interatomic bond, the lower the melt temperature of the material. d. Ionic and covalent bonds are non-directional in nature, while metallic bonds are highly directional. e. I would expect a material with a higher atomic packing factor to have a higher density than one with a lower atomic packing factor. f. Carbon has a higher diffusion coefficient in FCC Fe than in BCC Fe at the same temperature. Answers (True of False, write out complete word, please): a. ___________ b. ___________ c. ___________ d. ___________ e. ___________ f. ___________ Grades: #1__________ #2____________ #3____________ #4_________ Total____________ g. I would expect to see many grain boundaries in a polycrystalline material, but none in a single crystal or amorphous material. h. Carbon diffuses in Iron at a higher rate than Iron diffuses in Iron at a given temperature. i. Impurities always reduce the mechanical properties of a material. j. Materials I is my favorite course because I love to explore the process, structure and properties relationships of all materials! Answers (True of False, write out complete word, please): g. ___________ h. ___________ i. ___________ j. ___________
