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ME 302LCEE 370LMaterials MechanicsLaboratory ManualBy:Brendan J. O’TooleMohammad Kamal HossainLatest Revision8/26/2010Please forward corrections/suggestions to [email protected]

ME 302L Materials Mechanics LaboratoryCEE 370 L Engineering Mechanics of Deformable Bodies LabFall 2010Laboratory ManualThis is a downloadable pdf file with all information needed for this course.There is no other textbook.Lab Coordinator:Dr. Brendan O'Toole, Ph.D.,Associate Professor of Mechanical EngineeringSEB 2218, (702) 895 – 3885, [email protected] Department Laboratory Director:Mr. Jeff Markle, [email protected] B-162, (702) 895 - 5597Laboratory Sections and Instructors:CEE 370L 001, TBE B-150, Tuesday 8:30 AM – 11:20 AMMohamed Zeidan, [email protected] 370L 002, TBE B-150, Thursday 8:30 AM – 11:20 AMMohamed Zeidan, [email protected] 302L 001, TBE B-150, Tuesday 4:00 PM – 6:45 PMMuhammed Syful Islam, syful [email protected] 302L 002, TBE B-150, Friday 8:30 AM – 11:20 AMChristopher Carron, [email protected] labs are performed in TBE B-150.The Teaching Assistants (TA’s) usually run the entire lab including:instruction, grading, and evaluation of student performance.Contact the laboratory coordinator if there is a problem that cannot beresolved directly between the student and the TA.ii

Vishay Measurements Group Strain Gage WebsiteStrain Gage Installation ManualME 302 LAB SCHEDULEWeekDatesLab TopicsAssignment Due Dates18/23 - 8/27No Lab Classes28/30 - 9/3Overview, Safety,Uncertainty AnalysisStatistical Analysis39/6 - 9/10Tensile Testing Data Reduction Overview49/13 - 9/17Lab 1: Tensile Testing59/20 - 9/24Lab 2: Poisson’s RatioLab 169/27 - 10/1Lab 3: TorsionLab 2710/4 - 10/8Lab 4: Bending - Modulus of ElasticityLab 3810/11 - 10/14Lab 5: Strain Gage ApplicationLab 4910/18 - 10/22Lab 5: Strain Gage Application1010/25 - 10/29Group Lab Projects(NO FRIDAY LAB THIS WEEK)1111/1 - 11/5Lab 6: Beam DeflectionsLab 51211/8 - 11/12Group Lab ProjectsLab 61311/15 - 11/19Lab 7: Column Loading1411/22 - 11/26Group Lab Projects(NO Thurs/Fri. LABS THIS WEEK)1511/29 - 12/3Group Lab Projects1612/6 - 12/10Finals WeekHomework 1A and 1BLab 7iii

ME 302 Lab Grading (CE 370 Grading may be different)The grade for the lab will be divided as follows:Individual Lab Reports & Homework:HW 1a and 1b:Lab Report 1:Lab Report 2:Lab Report 3:Lab Report 4:Lab Report 5:Lab Report 6:Lab Report 7:Group Lab Report:Quizzes:Quiz 1 (Tensile Testing and Poisson’s Ratio):Quiz 2 (Torsion & Bending):Quiz 3 (Strain Gage Application):Quiz 4 (Beam Deflection and Column Loading):Attendance/Participation:56 %7%7%7%7%7%7%7%7%15 %20 %5%5%5%5%9%Individual Lab Reports & Homework: Follow the format guidelines found later in this manual and directions from the laboratory instructor. You cannot turn in a lab report if you did not attend and participate in the lab. Each lab report and homework assignment is graded with a maximum score of 100 pts. Late Reports:o 10 points are deducted from your score for each week-day that the report is late.o For example, you will lose 50 points if the report is 1 week late.o Reports will not be accepted if they are more than 1 week late.Group Lab Report: Each student will be a part of a group that plans and performs their own experiment. The lab TA must approve of all groups and projects before they are conducted.Quizzes: Four closed book, short quizzes will be scheduled throughout the semester.Attendance and Participation: The laboratory instructors will take attendance each week. They will also make note of enthusiastic participation, lack of participation, and/or leaving the lab early. They will assign a grade to each student at the end of the semester based on a combination of attendance andparticipation level in the class.Excused Absences:If you have a good reason to miss a lab, please contact your laboratory instructor ahead of time to makearrangements to make up the lab work.All ME students must meet their faculty mentors at least once in each semester to avoid any hold in theirregistration. Please contact department for the name of the faculty mentor. When your faculty mentor is notavailable, you can contact ME Department for an advice.iv

ME 302L / CEE 370LMaterials Mechanics LaboratoryLab Coordinator:Dr. Brendan O'Toole, Ph.D.,Associate Professor of Mechanical EngineeringTBE B-122, (702) 895 – 3885, [email protected] lab coordinator is responsible for: Planning the lab schedule each semester Coordinating the lab schedule with the lecture schedule as much as possible Revising and updating the laboratory manual Helping the Teaching Assistants (TA’s) prepare for the labs Resolving conflicts between students and TA’s (if necessary)ME Department Laboratory Director:Mr. Jeff Markle, [email protected] lab director oversees all of the ME undergraduate laboratories and isresponsible for: Maintenance of laboratory equipment (planned and emergency) Keeping track of laboratory supplies:o Strain gages and accessorieso Test Sampleso Soldering irons Keeping copies of equipment manuals Upgrading and installing new equipment Training students, staff, and faculty on new equipment as neededv

Table of ContentsME 302 / CEE 370 Sections and Teaching Assistants iiME 302 Lab Schedule (*Note that the CE370 schedule may be different) .iiiME 302 Lab Grading (*Note that the CE370 grading may be different) ivME 302 / CEE 370 Lab Coordinators and Director .vTable of ContentsviChapter 1: Overview of Laboratory Class Procedures .Overall Class Objectives . . .ME 302L / CEE 370 Course Policies .Laboratory Report Contents 1235Chapter 2: General Laboratory Safety Procedures .Laboratory and Machine Shop Safety Policies and Procedures .Material Safety Data Sheets (MSDS) and Hazardous Materials Shop Supplies .Emergency Phone Numbers .ME 302L / CEE 370 Lab Safety Procedures Signature Page .8914151617Chapter 3: Statistical and Uncertainty Analysis . .Statistics Summary and Example Problem . . .Uncertainty Analysis Summary and Example Problems .Homework Assignment (# 1A, Statistical Analysis Problem) Homework Assignment (# 1B, Uncertainty Analysis Problem .Homework Assignment (# 1C, Submit signed copy of page 17) .181928313232Chapter 4: Tensile Testing . . . .Objectives . Procedures .Data Reduction Guidelines (Laboratory # 1) .33343940Chapter 5: Poisson’s Ratio . . .Objectives .Procedures .Data Reduction Guidelines (Laboratory # 2) 44454646Chapter 6: Torsion . .Objectives .Procedures . .Data Reduction Guidelines (Laboratory # 3) .48495050vi

Chapter 7: Bending – Modulus of Elasticity . . .Objectives .Procedures Data Reduction Guidelines (Laboratory # 4) .56575859Chapter 8: Strain Gage Application . .Objectives .Procedures .Assignment (Submit working strain gaged specimen) .60616161Chapter 9: Beam Deflection . . .Objectives . Procedures .Data Reduction Guidelines (Laboratory # 5) .63646565Chapter 10: Column Buckling . . .Objectives . .Procedures .Data Reduction Guidelines (Laboratory # 6) .67686969vii

CHAPTER 1OVERVIEWOFME 302L (CEE 370L)CLASS PROCEDURESAND EXPECTATIONS1

ME 302 (CEE 370L) Course ObjectivesThe primary objective for this course is to provide hands on experimental experience in characterizingmechanical properties of materials. Students will learn: Laboratory safety procedures Uncertainty analysis of data (error propagation) Statistical analysis of data Laboratory report writing skills Tensile Testing Procedures for finding: Young’s Modulus, yield strength and strain, ultimatestrength and strain, and failure strength and strain of metallic materials Procedure for determining Poisson’s ratio of materials Flexure testing procedures for determining Young’s modulus Torsion testing procedures for determining shear modulus Flexure test procedures for determining beam deflections Column compression procedures for investigating buckling behaviorStudents will also perform a group project where they will propose and conduct their own laboratoryexperiment.2

MEG 302L (CEE370L) Class PoliciesPARTICIPATIONAttendance and active participation in the laboratory exercises are the only way to get the full learningexperience offered by this class. You are expected to be available for the entire time that your lab isscheduled and part of your grade will be based on attendance. The Teaching Assistant assigned to yourlab section will take attendance each week. You must contact the Teaching Assistant to discuss anyexcused absences and make-up labs if needed.Most of the laboratory experiments will be performed in groups due to the limited amount of space andthe number of test stations. Experimental data will be shared within your group but all group membersmust submit individual reports.SAFETY PROCEDURESYou are responsible for following all College of Engineering Laboratory and Machine Shop SafetyRules as outlined in detail in Chapter 2 of this manual.ASSIGNMENTSYou are responsible for following all College of Engineering Laboratory and Machine Shop SafetyRules as outlined in detail in Chapter 2 of this manual. Each student will submit one (1) homeworkassignment and six (6) lab reports. You might be working in groups in the lab but you will submitindividual reports. In addition, there will be one (1) group laboratory project with one report submittedfor the entire group.Lab Reports Reports are due on the date indicated in the lab schedule (one week after completion of thelaboratory)All lab reports are to be word processed, except the original data which will be included as anappendix.All graphs are to be computer generated. Provide a graph title, and label the axis and majorgraduations. Always provide units where applicable.Lab reports are to be structured as shown on the Laboratory Report Contents Sheet.All equations, graphs, tables, and figures are to be numbered, with the appropriate "call-out"reference within the text. Also provide a Table of Graphs and Figures immediately followingthe Table of Contents if the report has many figures.The reports will be graded on format, content, and grammar, so be sure you proofread (andspell check) your reports.3

1. Most reports should include an abstract, experimental procedure, results, analysis ofresults, and conclusions.2. Raw data should be included as an appendix if it can be formatted within a few pages. Ifyou have many pages of raw data in a computer file, do not append it to the report.Keep it somewhere safe for the semester and be prepared to send a copy or bring a copyto a classmate, teaching assistant, or other instructor if needed.3. The analysis of results should include uncertainty analysis of your experimentalmeasurements, statistical analysis of your data if 3 or more data points are available,and a comparison of experimentally obtained properties with expected results. Late lab reports are accepted at a penalty of 10% per day (excluding Saturday & Sunday).Reports will not be accepted more than one week late.Group Laboratory Project All students will participate in a Laboratory group project. The objective of this project is toprovide an opportunity for all students to participate in the process of designing an experiment.All topics must be approved by the Teaching Assistants. The groups must have between 4 and5 members. You cannot work alone; you must work in a group.The project should be a simple experiment that can be performed in 1-2 hours. Thepreparation, design of the experiment, gathering of materials, and selection of testfixtures may take longer. You must submit a brief description of your experimental plan toyour TA for approval before conducting the experiment. The plan should clearly state, thematerials you plan to use, the fixtures needed, the test procedure, and your plan for analyzingthe data.Lab projects must make use of the principles learned in ME 302 and must involve materialtesting using knowledge obtained in ME 302L.The project will require one written report for each group.Projects must be performed and reports submitted by the last day of regular classes in thesemester.4

Laboratory Report ContentsAll laboratory reports (except Lab # 1) must consist of the following:Title Page (Example at the end of this section)Table of ContentsList of Figures and List of Tables Necessary if the report has more than 5 figures or 5 tables.Abstract State the lab objectives. Provide a brief summary of the results.Introduction Provide background information regarding the experiment. Include the application of the experiment to theory. Indicate what the anticipated results of the experiment are, if known. In most cases, theoreticalvalues (from the tables in the book) are the anticipated results.Equations Engineering students need to know how to include computer generated equations in reports.Use Microsoft equation editor for generating equations in your lab reports.o The equation editor can be accessed by selecting the “Insert” tab from the menu bar,then select “Object”, then select “Microsoft Equation”. Equation symbols are selectedfrom the various menus.Experimental Procedure Describe the specimens tested (type of material, physical dimensions, etc.). Do not say thingslike, "these were the same specimens used in Lab # 2." Each lab report is a separate entity, andthe specimens must be fully described each time. Identify the instruments used, including manufacturer and model number. Provide a detailed description of the laboratory procedure used. Do not simply repeat theprocedure that I give to you; expand on it by explaining why something is done or howsomething is done. Include a sketch of the experiment setup. This may be hand drawn, but be neat.Results Identify the equations used to obtain the results. Present the results. Provide appropriate plots, graphs, and tables. Make sure the report "flows" from the beginning to the end of the experiment; don’t presentfinal results prior to intermediate calculations.5

Analysis of ResultsCalculate % error with the formula:% Error (Expected Results - Experimental Results) 100Expected Results.where,the expected results are found from tabulated data in a reliable source (textbook)or the expected results are determined from theoretical predictions. Indicate sources of error. Do not just say, "human error." Be specific.Specify the uncertainty of your calculations using methods described in the Statistics Lab.Specify the statistical variation (mean and standard deviation) of your results if 3 or moredata points are available.Conclusions State what the results mean. Was the experimental method used a valid one? Explain why or why not. Did you accomplish the objectives of the lab? This is not a "yes/no" question. You must explainhow the objectives were or were not met. Remember that you may not always get the "proper results" even though you followed theprocedure and performed the experiment properly.Appendices Provide all raw data collected in the lab (In other words, your original data sheet. This is handwritten, and will not be graded for neatness). DATA IS NEVER TO BE ALTERED. Provide a list of references.6

Laboratory NumberLaboratory TitlePrepared For:“Your Laboratory TA”, ME 302LDepartment of Mechanical EngineeringUniversity of Nevada, Las VegasPrepared By:Your NameYour Group MembersDate Laboratory Performed:Date Submitted:7

CHAPTER 2GENERALLABORATORYSAFETY PROCEDURES8

University of Nevada Las VegasHoward R. Hughes College of EngineeringMACHINE SHOP AND LABORATORY POLICIES AND PROCEDURESGeneral Safety GuidelinesThe following is not intended to be exhaustive, nor the final word about shop/laboratory safety, shopprocedures and policies. It is up to you, the individual, to be responsible for your safety and to followsound, sensible safety guidelines. We encourage and are open to your suggestions and comments.The purpose of this document is to familiarize all students/faculty/staff, who have a need to work in thelabs or shop, with safe operating procedures. OSHA, the State of Nevada (NIOSH) and UNLV all require,by law, that we include safety training, as part of your lab class instructions. Everyone that has a need touse chemicals will receive “HAZMAT” (hazardous materials) training from the UNLV environmentalhealth and safety office.Since it is possible for anyone to lose their limbs, eyes, or life due to an accident, simple carelessness oreven failing to use an inexpensive piece of safety apparel, UNLV Engineering College has implementedthese rules of conduct for all persons needing to use the shops and/or labs. As soon as a new safetytraining document is updated or completed, every student will receive a copy. Inasmuch as safety iseveryone’s responsibility, take the extra few seconds to equip yourself with the proper safety apparel to dothe job correctly, you may be thankful the rest of your life that you did. Think about having to live the restof your life knowing that you could have prevented your own or someone else’s dismemberment becauseyou didn’t do, say something, or think about safety.Although we are not 100% configured in accordance with all ADA laws covering disabled persons, wecan make nearly all adjustments that are required to accommodate any person on a case-by-case need. Ifyou have a documented disability, you are encouraged to contact the Disability Resource Center forassistance with your academic accommodations in the Reynolds Student Services complex in room 137.Their phone number is 895-08669

BASIC SHOP AND LABORATORY SAFETY RULESThese basic rules have been drafted because many of these infractions have been encountered here atUNLV and have resulted in an injury of some kind and even the loss of a life. We must strive to assurethat the loss of life or limb never happens again. These rules are not flexible and must be followed at alltimes, no exceptions, exemptions and no excuses and the penalties for flagrant violations are inflexibleand could impede your graduation efforts.1.2.3.4.5.6.7.8.9.10.12.13.14.15.No horseplay ever.No drugs or alcohol ever. (24 hours a day 7 days a week)There must be at least two persons in the shop or lab when working.Be considerate of the others working in your area. Keep noise to a minimum as other people workingin your area may be trying to conduct an experiment and don't want to be distracted by other peoplehaving a “party”.Do not approach or touch any machine operator from behind while any equipment is in operation. Ifyou must get their attention, first call to them from a distance so they may switch the machine offbefore being distracted by conversation. When talking with another person, always shut off allmoving or rotating equipment.Dress appropriately for shop or lab work. Loose and/or baggy clothing and long sleeve shirts are notto be worn when operating machinery. Keep in mind that some of the equipment turns at a high rateof speed and may catch your clothes and pull you into the machine. Dismemberment and death hasresulted in