CONCORDIA UNIVERSITY DEPARTMENT OF MECHANICAL AND INDUSTRIAL ENGINEERING MECH 423 – Casting, Welding, Heat Treating and NDT (3.5 Credits), Fall 2011Instructor: Dr. S. Narayanswamy Lecture Time: _ T _ _ _ 17:45 - 20:15Office: EV 004.124 Lecture Room: EV-11.119Phone: 848-2424 (7923) Office Hours: _ _ _ J _ 10:00 – 12:00e-mail: firstname.lastname@example.org Web site: http://users.encs.concordia.ca/~nrskumarLab Instructor: Mr. Ehsan Rezabeigi Teaching Assistant: Ms. Maniya AghasibeigOffice tel: EV 14.189, ext. 7040 Office tel: EV 14.165, Ext. 7038Other: 514-9930028 Home: 514-7557400Recommended Text Books:1. Materials and Processes in Manufacturing, E. Degarmo, J.T. Black and R.A. Kohser, Prentice- Hall, 10th Edition. (Earlier editions will be fine)2. Material Science and Engineering, W.D. Callister, 7th Edition, Wiley, 2007 (or similar).Related Material:• ASM Metals Handbook; Volumes 4 (Heat-Treating), 6 (Welding, Brazing and Soldering) and 15 (Casting).• Modern welding by Andrew D. Althouse, and Carl H. Turnquist, and William A. Bowditch.Lectures ScheduleWeek Chapter Lecture Topics th1 6 Sep ‘11 Degarmo Chp. 11 Introduction; Fundamentals of casting processes th2 13 Sep ‘11 Degarmo Chp. 11 Solidification of liquid metals; Patterns, Castings Design th3 20 Sep ‘11 Degarmo Chp. 12 Expendable mould casting th4 27 Sep ‘11 Degarmo Chp. 13 Multi-Use mould casting; Casting alloys th5* 4 Oct ‘11 Degarmo Chp. 4 Phase Diagrams; Phase changes (Callister Chp. 9 & 10) th6 11 Oct ‘11 Degarmo Chp. 5, 35 Heat treatments; Surface treatment (Callister Chp. 11) th7 18 Oct ‘11 Degarmo Chp. 30 Fundamentals of Joining Processes th8 25 Oct ‘11 Degarmo Chp. 30 Fundamentals of welding/brazing/soldering processes st9 1 Nov ‘11 Degarmo Chp. 31 Gas welding; Arc welding th10* 8 Nov ‘11 Degarmo Chp. 32 Resistance welding; Other welding processes th11 15 Nov ‘11 Degarmo Chp. 33, 34 Brazing & soldering; Weld effects/defects, joint design nd12 22 Nov ‘11 Degarmo Chp. 10 Non-Destructive Testing (NDT) th13 29 Nov ‘11 ReviewThere will be 2 midterm exams during the tutorial period of Weeks 5 and 10Assessment: Assessment Criteria Share towards final Presentation (topic to be discussed) 10 % 10 % Lab (Welding & Heat treatment of steel) 10 % 10 % Assignments (4) 15 % 15 % Exams: Midterm (optional) 15 % 0% Final 50 % (with Midterm) 65% (without Midterm) Total 100% (with Midterm) 100% (without Midterm)
BackgroundThis is a course aimed at Mechanical Engineering Students who will need to know how components(whether big or small, simple or complex) can be shaped by either casting or joining and the effectthat these processes have on the properties of the material. An engine block, a propeller, a gas turbineblade, a steel ship, are all made from materials and must all be shaped or assembled in some way.Casting liquid metals is often the only economical way of making some components and it isimportant that this versatile technique that can produce minute, intricate jewellery and also hugemechanical structures weighing several tonnes is understood as it is very susceptible to flaws, defectsand microstructural changes that can dramatically change the properties of the finished component.So as well as understanding the morphological (shaping) benefits of casting it is also imperative thatone understands the limitations of this process as the mechanical properties of a cast alloy are usuallyinferior to that of the wrought (worked) alloy.Welding is a technique by which metals and plastics can be joined. There are several other similarprocesses such as brazing and soldering and more recently, adhesive and diffusion bonding. In mostcases of design and manufacture, a final mechanical system is assembled from several componentsthus the techniques by which smaller parts, whether it be electronic devices for a circuit board or steelplates for a ship, can be joined together are of paramount importance in most areas of engineering.Again these joining techniques may appear straightforward but many of them can change theunderlying structure of the material and hence affect the final mechanical properties of the assemblyso it becomes important to understand how these processes, such as welding and brazing, work andwhat they are doing to the base material. In this way, the engineer can use them to his/her advantagerather than, as is often the case with people without this understanding, weaken and degrade anassembly by inappropriate choice, technique or positioning of joining method.In some cases it is possible for the engineer to change some of the mechanical properties (principallystrength and hardness) of a component without changing the shape. As detailed in Mech 321, cold-working of a metal can significantly increase these properties but requires a change in componentshape. If an alloy has been cast into near-final shape then this technique is inappropriate however insome cases it is possible to improve properties through heat-treatment processes. These can includequenching and tempering, carburising and nitriding. The ability to markedly change the strength,hardness, ductility and toughness of a material by a simple heating and cooling cycle is very powerfuland if used properly is a great bonus to mechanical engineering but if it is not understood it can makefor horrendous and costly mistakes.Any engineer who is designing or using components needs to know not just how to make things butthe effect that these processes have on the final product.Learning Outcomes:By the end of this course, you should have: • an understanding of the main processes by which metals (and plastics) can be cast; • an understanding of the properties and possible defects of cast materials. • an understanding of the main thermal processes by which metals can be joined; • an understanding of the principal heat-treatment processes;This course should be seen as part of the whole process of Design and Production in that the shapingor joining of components will influence the designs possible, the mechanics of the system, the ease ofmanufacture and finally the performance of the product.Note: This course does not cover mechanical shaping of metals as these are covered in Mech 421.
Midterm Exam:During the tutorial period of week 5 (4th Oct) and week 10 (8th Nov) two midterm examinations willbe held. The midterm tests are not mandatory but are recommended. If the cumulative midterm resultis better than the one from the final exam, it will be counted for 15% towards the final grade.Laboratory:There is a laboratory component to this course. The aim of this lab is to illustrate the various types ofwelding and the effects of heat treatment processes on the mechanical properties of bare and weldedmetals and then how these effects may or may not be reversed. Mr. Peter Sakaris (Extn. 3153) will besupervising this in the Materials Laboratory (H-1058/59). A lab manual, prepared by Mr. PeterSakaris is available for purchase at the COPY CENTER, and the labs commence the week ofSeptember 12 (Week 1)Presentation:Each student/group will select a topic related to this course (and approved by the Instructor) and willprepare a 15 minute PowerPoint presentation giving an overview of the subject, major advantages/disadvantages, applications etc. Towards the end of term, time will be set aside in the tutorialsession(s) for each student/group to make their presentation to the rest of the class. Each talk will befollowed by a short question period. Each student/group will submit an hardcopy of the project reporton the last day of the classes 29th Nov 2011, prior to presentation. Marks will be awarded for:• Presentation style (audibility, structure, clarity, quality of visual aids etc.)• Technical content (showing understanding of subject, grasp of key points, explanation etc.)Preliminary Assessment Schedule:Sept 21st 5pm Assignment #1Oct 4th 8.30pm Midterm 1Oct 12th 5pm Assignment #2Oct 26th 5pm Assignment #3 thNov 8 8.30pm Midterm 2Nov 23rd 5pm Assignment #4 thNov 29 5.45pm Project ReportDeadline for submission for laboratory work is available in the Lab Manual. Work must be submittedto the tutor directly on or before due date. NO DELAYS/EXTENSIONS. Good presentation,including legibility, spelling and grammar, is expected for all work.Coursework – Certificate of OriginalityIn keeping with the Faculty policy, all coursework submitted as part of this course must have theCertificate of Originality form filled-in appropriately and attached as the cover page. The form isavailable on the following website: http://www.encs.concordia.ca/scs/Forms/expectations.pdfNOTE"In the event of extraordinary circumstances beyond the Universitys control, the content and/orevaluation scheme in this course is subject to change".