ME 350 Design for Manufacturability Instructor: Bruce Flachsbart, email: mems@illinois.edu office hours: M

1. ME 350 – Lecture 1 – Chapter 1 & 2 ME 350 Design for Manufacturability Instructor: Bruce Flachsbart, email: mems@illinois.edu office hours: Mon: 1-2, 3:30-4:30, Wed: 3:30-4:30, office: 221A MEB Lab TA’s: Phillip Poisson; Chris Olenek; Tarun Malik; Ramin Rasoulian; Oksen Baris; Ming Huo Labs will meet in 1227 MEL starting next week, Jan 25 - 29th

2. Textbooks & References Groover, M. P., Fundamentals of Modern Manufacturing, Third Edition, John Wiley, 2007 (Available at IUB and Folletts) Make sure you have the DVD with the book. References (available at engineering library): 1) Kalpakjian, S., and Schmid, S.R., Manufacturing Processes for Engineering Materials, Addison Wesley, 4th edition, 2003 2) Callister, W. D, Materials Science and Engineering, Wiley, 2003 3) Devor, Statistical Quality Design & Control, 2006

3. Grading and Homework Policy Grading: Homework 25% Hour Exams 25% Labs 20% Final Exam 30% Grade Distribution: A to A-: 25-35%, B+ to B-: 35-45% C+ to C-: 20-30%, D to F: < 5% Homework Policy: • HW turned in by 2:59 pm in class on the date due (mostly Tue). • HW 10% penalty after 3 pm, 20% after 5 pm, and not accepted after 1 pm Wednesday Lecture Notes: • Missed lecture material (with medical excuse) can be gone over during office hours

4. Three Hour Exams and Final: • In class, close book and notes. Only pencil(s), an eraser, and a calculator are allowed at your desk. Dates: • Typical problems: true/false, short answer, and quantitative analysis (equation sheet provided). • Phone calls or writing after time called will cost per minute or phone call. • Makeup exams: with medical excuse only.

5. Topics Covered (~30 chapters): • Material properties • Rapid prototype • Machining – CNC/Abrasive/Nontraditional • Molding • Casting • Composite manufacturing • Welding/Soldering/Joining • DFA • MEMS

6. Manufacturing History (part 1) • Late middle ages (1400’s) – birth of the middle class & people specialize into professions • 1439 → • 1760-1830 Industrial Revolution typified by the “” • Manufacturing is moved from home based “handicraft” to assembly in “” • The James Watt steam engine replaces water, wind, & animal power as the primary energy source • Cotton Processing (Spinning Jenny, Cotton Gin, Power Loom) brought about the birth of the • Iron foundries are built where coke replaces charcoal and bar iron enables potting and stamping • The Eli Whitney muskets demonstrate the viability of assembly

7. Manufacturing History (part 2) • 1850-1910 SecondIndustrial Revolution typified by “” • Mass production of steel enables railroads and big machinery • “Canning” of foods – birth of food processing • Birth of the chemical industries including petroleum refining • Factories get electrical power enabling longer work hours ( also invented) • Assembly line manufacturing • The internal combustion engine and the birth of the automobile industry (, 1885) • Scientific management of manufacturing brings about the birth of the field:

8. Manufacturing History (part 3) • 1980-present Third Industrial Revolution identified by the “” • Birth of automation • Expanse of multinational corporations and offshore production • Forth Industrial Revolution?

9. Manufacturable Materials • Metals • Steel, iron, nonferrous metals and alloys. • Polymers • Three catagories: • Ceramics • Glasses (i.e. ), and crystalline ceramics. • Composites • Mixtures of the other three types

10. Figure 1.4 Classification of Manufacturing Processes

11. Processing Operations • Increases workpart’s value by altering: • shape, • physical property, • appearance • Three categories: • Shaping operations (e.g. etc.) • Property-enhancing operations (e.g. • Surface processing operations (e.g. , etc.)

12. Assembly Operations Two or more separate parts are joined to form a new entity Types of assembly operations: • Joining processes – create a joint • Welding, brazing, soldering, and adhesive bonding • Mechanical assembly – fastening by mechanical methods • Threaded fasteners (screws, bolts and nuts); press fitting, expansion fits

13. What is DFM? • Design for Manufacturability (DFM): By understanding and analyzing the fundamental manufacturing processes, reduce the of production while achieving optimal product • Quality and lifetime of the products should not be left until the test stage, but actively brought into consideration by design, manufacture and assembly. • Rule of 10: order of magnitude increase on the cost of repair when changes are made at later stages (from parts → subassembly → assembly → final product on market → customer)

14. Ch 2 – The Nature of Materials • Crystal structure • Repeated geometric unit is called: • Characteristic of virtually all metals, some polymers, and some ceramics. • Defects • Point, line, and surface defects • Stress & Strain • Calculations • Crystalline vs noncrystalline • Another name for noncrystalline:

15. Crystal Structures in Metals • Body-centered cubic (BCC) e.g. Chromium, Iron, Molybdenum, Tungsten • Face centered cubic (FCC) e.g. Aluminum, Copper, Gold, Lead, Silver, Nickel • Hexagonal close-packed (HCP) e.g. Magnesium, Titanium, Zinc How many atoms in each unit cell?

16. Imperfections (Defects) in Crystals • Point defects: • Line defects: • Surface defects: • Grain boundaries or the surface of a crystal

17. Elastic & Plastic Strain When a crystal experiences a gradually increasing stress, it first deforms elastically, then atoms change lattice positions, and the deformation isplastic, or a permanent change.

18. Effect of Dislocations on Strain • As compared to a perfect lattice, the stress required for plastic deformation of a material with dislocation is: Figure 2.12 Effect of dislocations in the lattice structure under stress

19. Slip on a Macroscopic Scale • Slip occurs many times over throughout the metal when subjected to a deforming load, thus causing it to exhibit its macroscopic behavior in the stress-strain relationship • Dislocations are a good‑news‑bad‑news situation • Good news in manufacturing – the metal is easier to form • Bad news in design – the metal is not as strong as the designer would like • HCP has the fewest slip directions (thus usually has ductility), then FCC, and BCC has the most.

20. Polycrystalline Nature of Metals • A block of metal may contain millions of individual crystals, called: • Such a structure is called: • Each grain has its own unique lattice orientation; meeting at interfaces called: • Faster cooling of molten metal produces grain sizes that are: • Smaller grain size generally means that strength, hardness, and ductility are:

21. Crystalline versus Noncrystalline Figure 2.14 (a) crystalline and (b) noncrystalline materials. The crystal structure is regular, repeating, and denser; the noncrystalline structure is less tightly packed and random.

22. Volumetric Effects Tm – Tg – Amorphous and Crystalline structures differ in both melting and thermal expansion characteristics Figure 2.15 Characteristic change in volume for a pure metal (a crystalline structure), compared to the same volumetric changes in glass (a noncrystalline structure).

23. Summary • Attend lectures, be on time, read chapters, and participate. • We are going to cover a lot of manufacturing processes – their strengths and weaknesses. • We are going to cover the tools to understand and optimize manufacturing. • This class is to help you be able to better design a product for manufacturing.

24. Quotes • Be modest, a lot was accomplished before you were born. • Judge success by the degree that you’re enjoying peace, health, and love. • Take charge of your attitude. Don’t let someone else choose it for you. • Be forgiving of yourself and others. • Use wit to amuse, never abuse.