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Test your basic knowledge |
Engineering Materials
Start Test
Study First
Subject
:
engineering
Instructions:
Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can
study here
.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.
This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Second phase particles with n > glass.
Opacifiers
Impact - Toughness
Stress Intensity Factor
Incoherent
2. Growing interconnections to connect devices -Low electrical resistance - good adhesion to dielectric insulators.
Metals: Resistivity vs. T - Impurities
Metallization
Generation of a Magnetic Field - Within a Solid Material
Two ways to measure heat capacity
3. Different orientation of cleavage planes in grains.
Domains in Ferromagnetic & Ferrimagnetic Materials
Why fracture surfaces have faceted texture
Why materials fail in service
Diamagnetic Materials
4. Emitted light is in phase
Thermal Shock Resistance
Stress Intensity Factor
Hardness
Coherent
5. Small Coercivities - Used for electric motors - Example: commercial iron 99.95 Fe
Stress Intensity values
Paramagnetic Materials
Electromigration
Soft Magnetic Materials
6. Is reflected - absorbed - scattered - and/or transmitted: Io=It+Ia+Ir+Is
Incident Light
Thermal Conductivity
Plastic Deformation (Metals)
Translucent
7. 1. Hard disk drives (granular/perpendicular media) 2. Recording tape (particulate media)
Griffith Crack Model
Magnetic Storage Media Types
Reflection of Light for Metals
Domains in Ferromagnetic & Ferrimagnetic Materials
8. Created by current through a coil N= total number of turns L= length of turns (m) I= current (ampere) H= applied magnetic field (ampere-turns/m) Bo= magnetic flux density in a vacuum (tesla)
The three modes of crack surface displacement
Opaque
Generation of a Magnetic Field - Vacuum
There is no perfect material?
9. 1. Fluorescent Lamp - tungstate or silicate coating on inside of tube emits white light due to UV light generated inside the tube. 2. TV screen - emits light as electron beam is scanned back and forth.
Lithography
Influence of Temperature on Magnetic Behavior
High impact energy
Luminescence examples
10. Occurs at a single pore or other solid by refraction n = 1 for pore (air) n > 1 for the solid - n ~ 1.5 for glass - Scattering effect is maximized by pore/particle size within 400-700 nm range - Reason for Opacity in ceramics - glasses and polymers.
Scattering
What do magnetic moments arise from?
Thermal Conductivity
Charpy or Izod test
11. 1. Tc= critical temperature- if T>Tc not superconducting 2. Jc= critical current density - if J>Jc not superconducting 3. Hc= critical magnetic field - if H > Hc not superconducting
There is no perfect material?
Heat Capacity from an Atomic Prospective
Magnetic Storage Media Types
Critical Properties of Superconductive Materials
12. Measures Hardness 1. psia = 500 x HB 2. MPa = 3.45 x HB
Intrinsic Semiconductors
Extrinsic Semiconductors
HB (Brinell Hardness)
LASER
13. 1. General yielding occurs if flaw size a < a(critical) 2. Catastrophic fast fracture occurs if flaw size a > a(critical)
Shear and Tensile Stress
Engineering Fracture Performance
Two kinds of Reflection
Reflection of Light for Metals
14. If a material has ________ - then the field generated by those moments must be added to the induced field.
Modulus of Rupture (MOR)
Internal magnetic moments
Brittle Ceramics
Transgranular Fracture
15. Cp: Heat capacity at constant pressure Cv: Heat capacity at constant volume.
Stages of Failure: Ductile Fracture
Liquid Crystal Displays (LCD's)
Two ways to measure heat capacity
Etching
16. Cracks propagate along grain boundaries.
Heat Capacity from an Atomic Prospective
Luminescence examples
Why do ceramics have larger bonding energy?
Intergranular Fracture
17. A three terminal device that acts like a simple "on-off" switch. (the basis of Integrated Circuits (IC) technology - used in computers - cell phones - automotive control - etc) - If voltage (potential) applied to the "gate" - current flows between th
Opacity
Brittle Ceramics
The Transistor
Generation of a Magnetic Field - Within a Solid Material
18. Width of smallest feature obtainable on Si surface
The Transistor
Linewidth
Internal magnetic moments
High impact energy
19. Resistance to plastic deformation of cracking in compression - and better wear properties.
Meissner Effect
Large Hardness
Incoherent
Where does DBTT occur?
20. Increase temperature - increase in interatomic separation - thermal expansion
Thermal Expansion: Asymmetric curve
Luminescence
Why materials fail in service
4 Types of Magnetism
21. 1. Imperfections increase resistivity - grain boundaries - dislocations - impurity atoms - vacancies 2. Resistivity - increases with temperature - wt% impurity - and %CW
Two kinds of Reflection
Metals: Resistivity vs. T - Impurities
Not severe
Thermal Conductivity
22. Reflectiviy is between 0.90 and 0.95 - Metal surfaces appear shiny - Most of absorbed light is reflected at the same wavelength (NO REFRACTION) - Small fraction of light may be absorbed - Color of reflected light depends on wavelength distribution of
Refraction
Reflection of Light for Metals
LASER
True Stress
23. Allows flow of electrons in one direction only (useful to convert alternating current to direct current) - Result: no net current flow
Conduction & Electron Transport
Opacity
Hysteresis and Permanent Magnetization
IC Devices: P-N Rectifying Junction
24. Materials change size when temperature is changed
There is no perfect material?
Thermal expansion
Etching
Hard Magnetic Materials
25. - The emission of light from a substance due to the absorption of energy. (Could be radiation - mechanical - or chemical energy. Could also be energetic particles.) - Traps and activator levels are produced by impurity additions to the material - Whe
Lithography
Film Deposition
Luminescence
Ductile-to-Brittle Transition
26. 1. Ability of the material to absorb energy prior to fracture 2. Short term dynamic stressing - Car collisions - Bullets - Athletic equipment 3. This is different than toughness; energy necessary to push a crack (flaw) through a material 4. Useful in
Ductile-to-Brittle Transition
Conduction & Electron Transport
Impact - Toughness
Stages of Failure: Ductile Fracture
27. Specular: light reflecting off a mirror (average) - Diffuse: light reflecting off a white wall (local)
Etching
Two kinds of Reflection
Liquid Crystal Displays (LCD's)
Opaque
28. Liquid polymer at room T - sandwiched between two sheets of glass - coated with transparent - electrically conductive film. - Character forming letters/ numbers etched on the face - Voltage applied disrupts the orientation of the rod- shaped molecule
Why materials fail in service
Reflection of Light for Metals
Impact energy
How an LCD works
29. Found in 26 metals and hundreds of alloys & compounds - Tc= critical temperature = termperature below which material is superconductive.
Superconductivity
True Strain
Transgranular Fracture
Yield and Reliability
30. Occur when lots of dislocations move.
Thermal Conductivity
Brittle Fracture
Slip Bands
Thermal expansion
31. Increase temperature - no increase in interatomic separation - no thermal expansion
Where does DBTT occur?
True Stress
Thermal Expansion: Symmetric curve
Why fracture surfaces have faceted texture
32. Growth of an oxide layer by the reaction of oxygen with the substrate - Provides dopant masking and device isolation - IC technology uses 1. Thermal grown oxidation (dry) 2. Wet Oxidation 3. Selective Oxidation
Thermal Stresses
Insulators
Oxidation
Lithography
33. These are liquid crystal polymers- not your normal "crystal" -Rigid - rod shaped molecules are aligned even in liquid form.
34. Occur due to: restrained thermal expansion/contraction -temperature gradients that lead to differential dimensional changes sigma = Thermal Stress
Griffith Crack Model
Thermal Stresses
Modulus of Rupture (MOR)
Dependence of Heat Capacity on Temperature
35. Cracks pass through grains - often along specific crystal planes.
Why do ceramics have larger bonding energy?
Magnetic Storage
Rockwell
Transgranular Fracture
36. Undergo little or no plastic deformation.
Magnetic Storage Media Types
Where does DBTT occur?
Elastic Deformation
Brittle Materials
37. They are used to assess properties of ceramics & glasses.
Response to a Magnetic Field
Film Deposition
Brittle Materials
Bending tests
38. Undergo extensive plastic deformation prior to failure.
Hardness
Ductile-to-Brittle Transition
Ductile Materials
Elastic Deformation
39. - Metals that exhibit high ductility - exhibit high toughness. Ceramics are very strong - but have low ductility and low toughness - Polymers are very ductile but are not generally very strong in shear (compared to metals and ceramics). They have low
Stress Intensity values
Translucent
Liquid Crystal Displays (LCD's)
Hard Magnetic Materials
40. Diffuse image
Stress Intensity Factor
LASER
Translucent
Charpy or Izod test
41. 1. Necking 2. Cavity formation 3. Cavity coalescence to form cracks 4. Crack propagation (growth) 5. Fracture
Stages of Failure: Ductile Fracture
Stress Intensity Factor
Metallization
Thermal Conductivity
42. Light Amplification by Stimulated Emission of Radiation
LASER
How to gage the extent of plastic deformation
IC Devices: P-N Rectifying Junction
The Transistor
43. The Magnetization of the material - and is essentially the dipole moment per unit volume. It is proportional to the applied field. Xm is the magnetic susceptibility.
How to gage the extent of plastic deformation
Fourier's Law
M is known as what?
Coefficient of Thermal Expansion
44. Defines the ability of a material to resist fracture even when a flaw exists - Directly depends on size of flaw and material properties - K(ic) is a materials constant
Electromigration
Intergranular Fracture
Plastic Deformation (Metals)
Stress Intensity Factor
45. These materials are "attracted" to magnetic fields.
Magnetic Storage
Paramagnetic Materials
Metallization
Stress Intensity Factor
46. Is analogous to toughness.
True Stress
Impact energy
Linewidth
Ductile Fracture
47. Metals are good conductors since their _______is only partially filled.
Valence band
There is no perfect material?
Magnetic Storage
Heat Capacity from an Atomic Prospective
48. Ohms Law: voltage drop = current * resistance
What do magnetic moments arise from?
Incident Light
Electrical Conduction
Shear and Tensile Stress
49. Specific heat = energy input/(mass*temperature change)
Intergranular Fracture
Not severe
Superconductivity
Specific Heat
50. The size of the material changes with a change in temperature - polymers have the largest values
Charpy or Izod test
Hard Magnetic Materials
Coefficient of Thermal Expansion
Ductile-to-Brittle Transition