Download Midterm Exam 1 Sheet | Fundamentals of Materials - Spring 2014 | ENGR 220 and more Exams Materials science in PDF only on Docsity! Page 1 ENGR 220 Midterm 1 Exam Sheet Spring 2014 DO NOT PUT ANSWERS ON THIS SHEET. DO NOT TURN IN THIS SHEET. You will have 55 minutes for this exam. It is a closed‐book and closed‐note exam. You may not use a calculator for this exam. Useful formulae and constants as well as periodic tables are provided on the reverse side of this page. ALL ANSWERS AND WORK MUST BE SHOWN ON THE ANSWER SHEET IN ORDER TO EARN CREDIT! For the questions on this page, use the word bank on your answer sheet to choose the correct answer. Write the number of correct word from the bank in the corresponding space on the first page of the answer sheet. Words from the word bank may be used for more than one answer. Each correct answer earns 2 points. I. Two metallic crystal structures are described as being close‐packed. a. What are the abbreviations for these two crystal structures? 1. ____ and 2. ____ b. What are the corresponding atomic packing factors (in the same order)? 3. ____ and 4. ____ II. Which elemental property can be used to determine if a bond between two elements is ionic or covalent? 5. ___ III. Geckos are able to “stick” to surfaces as they climb. This is due to 6. ___ bonding. IV. In ionic bonding, electrons are transferred in order to create a positively charged 7. ___ and a negatively charged 8. ___. The attraction between these ions can be quantitatively evaluated using 9. ___ law. V. Which type of bonding would be most prevalent for CsCl? 10. ____ VI. Which type of bonding would be most prevalent for CO2? 11. ____ VII. In which class of material can secondary bonding be found (choose one)? 12. _____ VIII. Depending on several factors during cooling, the resultant grain structure can be equiaxed leading to 13. ____ properties in a metal or the resultant grain structure can be columnar leading to 14. ___ properties in a metal. IX. During class, we watched a video where a steel wire was heated causing it go from a room‐temperature BCC phase to a high‐temperature FCC phase. Upon cooling, the wire expanded slightly when it reached 912°C. What is the name of the phenomenon for materials having more than one crystal structure? 15. ____ X. Three point defects that were discussed in lectures were: 16. ____ 17. ___ and 18. ____ XI. What is the name of the type of equation that is used to describe many thermally activated process? 19. _____ XII. The Burgers vector of a 20. _______ is parallel to the dislocation line. XIII. Which of the microscopy techniques could be used to observe grain boundaries? (list all that are applicable) 21. _____________ XIV. In materials science and engineering, we are interested in the linkage between four aspects of materials. Fill in the blanks in the correct order for credit: XV. As discussed in lectures, single crystal metals will usually have anisotropic properties and will not contain which planar defect? 25. _______ THE REST OF THE EXAM QUESTIONS CAN BE FOUND ON YOUR ANSWER SHEET.