ENMF 417 Midterm 1 Flashcards

61 flashcards · Other · by Dylan Matwe

1. Tribology Describes

   Friction, Wear, Lubrication

2. 3 Types of Wear

   Adhesion, Abrasion, Chemical/Corrosion, Fatigue

3. Lubrication Effects

   Coolant, Thermal Barrier, Lube, Chip Removal

4. Surface Treatments

   Shot Peening, Painting, Anodization, Electro Plating, Vapor D, Case Hardening

5. What's bad for Fatigue Life?

   Welding, EDM, Plating, Grinding, Hardening

6. What's good for Fatigue Life

   Shot Peening Case Hardening Burninsing Polishing Cold Rolling Honing

7. What are methods of Non Destructive Desting

   Xray / Acoustic Eddy Current Magnetic Flux Ultrasound

8. Up Milling:

   Rough Pass

9. Down Milling

   Finishing Pass

10. Causes of Tool Wear:

    High Temp Friction Chemical RxN

11. Tool Wear Types

    Adhesion Diffusion (Crater) Abrasion

12. What causes Adhesion tool wear

    Soft Material Sharp Tool @ High RM Chemical Casting

13. Types of cutting fluid

    Lube Coal Debris

14. High Strength Steel

    High Toughness Low Hardness Regrind/reverse Carbide

15. Carbide Properties

    High Strength Wear Resistant Hardness Thermal Conditioning Low Toughness

16. Ceramic

    Chemically Strengthened Wear Resistant Finishing

17. Ways to reduce cost of engineering changes

    Simplify Larger Tolerance Less expensive materials Alternative methods of mfg More efficient machines

18. Thin Cross Section Difficulties w/ Castin & Injection Molding

    Mold Filling Dimensional Accuracy

19. Forging Thin Cross Section Difficulties

    Require higher force due to friction between die and workpiece

20. Sheet metal Thin Cross Section Difficulties

    Casuses wrinkling

21. Machining Thin Cross Section Difficulties

    Deflection, vibrations -> chatter

22. Welding Sheet metal Thin Cross Section Difficulties

    Distrotions due to thermal gradient

23. Casting and injection thick cross section difficulties

    Casting and Injection molding

24. What is ductility

    Length of the stress strain curve

25. How does temperature impact material properties?

    Higher Ductility, Higher Toughness, lower stress, lowers UTS, lower n (strain hardening exponent)

26. Methods to prevent fatigue faliure

    Shot Peening Polishing the surface Minimize vibration

27. Creep

    Permanent deformation due to static loading

28. Residual Stress (RS)

    Left over stress, Compressive RS is good for fatigue, Tensile is bad for fatigue

29. Profilometer

    Rides the top of a surface

30. Surface Roughness

    Arithmeti average of the deviation of the surface from a datum

31. Tribology

    Study of surfaces, involves friction, wear and lubrication

32. Friction

    Resistance of 2 bodies sliding

33. Adhesive Wear

    Due to adhesion between 2 surfaces

34. Abrasive wear,

    Caused by hard and rough surface sliding along each other and forming chips

35. Corrosive Wear

    Chemical Reactions between surface and environment

36. Fatigue wear

    Caused when surface of a part is subjected to cyclic loading

37. What variables impact the sliding of 2 materials

    Contract Pressure Speed Temperature

38. What are the function of metal lubrication?

    Decreases Friction and Wear Increases Material flow in tools and dies Acts as a thermal barrier Cooling Removes Debris/chips

39. What are different Surface Treatments

    Shot peening Case Hardening (carburizing) Vapor Deposition (PVD, CVD, Sputtering) Electroplating Anodizing - Oxidation Process Painting

40. Shot Peening

    Workpiece is impacted with a bunch of balls, induces plastic surface deformation and work hardening /compressive residual stresss

41. What is PVD

    Physical Vapor Deposition Particles are physically depositied onto parts which creates a barrier

42. What is (CVD)

    Chemical Vapor Deposition Thermo Chemical Process is used to coat TiCl_4 (v) N and H Thicker than PVD Longer Process, but has better quality

43. Electroplating

    Material is deposited using charged anode and cathode

44. CMM

    Computer Measurement Machine Probe attached to head records all measurements

45. Laser Doppler Vibrometere

    Speed Gun Reflected laser beam has a frequency shift

46. SEM

    Scanning Electron Microscope Electrons measure

47. AFM

    Atomic Foce Microscope, Scans the surface

48. What is AE

    Acoustic Emssionns testing Sounds made by a materal are used to analyze it's health Could hear Friction Crack Growth Material Reactions

49. Eddy Currents

    When the eddy currents are distorted, the impedance in a coil is alterd. This indicates a material flaw or material condition.

50. What is MFL

    Magnetic Flux Leakage Metal is magnettized, and then leaks are detected

51. Pros of Machining

    Dimensional Accuracy Complex Shapes Surface finish Can process a variety of materials Can be economical for small batch

52. Cons of Machining

    Expensive for large batch Wastes materials Lubricants Time intensive Bad for surface integrity

53. What parameters impact forces

    RPM, depth, width, Feed rate, tool geometries, lubricants

54. What causes tool wear

    HIgh localized Stresses High Temp Abrasions Chemical Reactions

55. Abrasion Wear def and sultions

    Also called flank wear When the hard tool material wears away due to rubbing of the tool along macined surface Solution: High speed Sharper tool Coating Coolants

56. Diffusion Wear def and solutions

    Also called Crater Wear Caused by high temps at tool-chip interface and chemical affinity between the tool and workpiece Solution: Protective coatin

57. HSS Properties

    Cheap High Toughness Low Hardness Regrind + Reuse

58. Carbide Properties

    Tungesten Carbide Good Compressive strength Good hardness Good Wear Resistance Good thermal conductivity Lower toughness than HSS

59. Ceramic/cerments tool properties

    Aluminum Oxide Higher wear resistance & hot harness Very Chemically Stable Used for finishing of hardened steel

60. PCD properties

    Polycrstalline Diamond The hardest material Low friction Wear resistance Expensive Ued for non-ferrous metals BAD for steel plates

61. CBN tool properties

    Cubic Boron Nitride Second hardes High wear resistance Low touchness Chemically inert to iron & nickel