Tensile Strength - Material Science and Engineering - Exam, Exams of Material Engineering

Download Tensile Strength - Material Science and Engineering - Exam and more Exams Material Engineering in PDF only on Docsity! - 1 - CORK INSTITUTE OF TECHNOLOGY INSTITIÚID TEICNEOLAÍOCHTA CHORCAÍ Autumn Examinations 2009 Module Title: Material Science & Engineering Module Code: MECH6012 School: Mechanical & Process Engineering Programme Title: Bachelor of Engineering (Honours) in Mechanical Engineering – Year 1 Bachelor of Engineering (Honours) in Biomedical Engineering – Year 1 Programme Code: EMECH_8_Y1 EBIOM_8_Y1 External Examiner(s): Mr. Peter Clarke, Prof. Robin Clarke Internal Examiner(s): Dr Gerard Kelly Instructions: Answer any three questions. All questions carry equal marks Note if you attempt question 3 please return the equilibrium diagram with your answer book. Duration: 2 Hours Sitting: Autumn repeat Requirements for this examination: Note to Candidates: Please check the Programme Title and the Module Title to ensure that you have received the correct examination paper. If in doubt please contact an Invigilator. - 2 - Q1. (a) A cylindrical specimen of aluminum having a diameter of 12.8 mm and a gage length of 50.80 mm is pulled in tension. Use the load vs. elongation data shown in the table below to answer the questions posed in parts (i) through (v). N mm 0 50.800 7330 50.851 15100 50.902 23100 50.952 30400 51.003 34400 51.054 38400 51.308 41300 51.816 44800 52.832 46200 53.848 47300 54.864 47500 55.880 46100 56.896 44800 57.658 42600 58.420 36400 59.182 (i.) Plot the data as engineering stress vs. engineering strain. (5 marks) (ii.) Compute the modulus of elasticity. (4 marks) (iii.) Determine the yield strength at a strain offset of 0.002. (4 marks) (iv.) Determine the tensile strength of this alloy. (4 marks) (v.) What is the approximate ductility, in percent elongation? ( 4 marks) (b) Using the data presented in table 1 above. generate a true stress strain plot for aluminum. Measured diameters are given below for the last four data points, which should be used in true stress computation. (12 marks) Length Diameter N mm (mm) 46100 56.896 11.71 44800 57.658 10.95 42600 58.42 10.62 36400 59.182 9.4