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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. Occur when lots of dislocations move.
Slip Bands
Not severe
Opacifiers
Film Deposition
2. To build a device - various thin metal or insulating films are grown on top of each other - Evaporation - MBE - Sputtering - CVD (ALD)
True Stress
Plastic Deformation (Metals)
Film Deposition
Generation of a Magnetic Field - Within a Solid Material
3. These materials are "attracted" to magnetic fields.
Paramagnetic Materials
Stages of Failure: Ductile Fracture
Thermal Expansion: Symmetric curve
Hardness
4. Measures impact energy 1. Strike a notched sample with an anvil 2. Measure how far the anvil travels following impact 3. Distance traveled is related to energy required to break the sample 4. Very high rate of loading. Makes materials more "brittle."
Opacity
Charpy or Izod test
Valence band
IC Devices: P-N Rectifying Junction
5. Allows flow of electrons in one direction only (useful to convert alternating current to direct current) - Result: no net current flow
IC Devices: P-N Rectifying Junction
Linewidth
Brittle Materials
Opaque
6. 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
Color
Magnetic Storage
Reflectance of Non-Metals
7. -> fluorescent light - electron transitions occur randomly - light waves are out of phase with each other.
Electromigration
Translucent
Heat Capacity from an Atomic Prospective
Incoherent
8. These materials are relatively unaffected by magnetic fields.
Diamagnetic Materials
Plastic Deformation (Metals)
Film Deposition
Fatigue
9. The ability of a material to absorb heat - Quantitatively: The energy required to produce a unit rise in temperature for one mole of a material.
Insulators
Opacifiers
Etching
Heat Capacity
10. Cracks propagate along grain boundaries.
Impact - Toughness
M is known as what?
Intergranular Fracture
Brittle Fracture
11. No appreciable plastic deformation. The crack propagates very fast; nearly perpendicular to applied stress. Cracks often propagate along specific crystal planes or boundaries.
Bending tests
Brittle Materials
Brittle Fracture
Metallization
12. A measure of the ease with which a B field can be induced inside a material.
Influence of Temperature on Magnetic Behavior
How an LCD works
Relative Permeability
To improve fatigue life
13. The ability of a material to be rapidly cooled and not fracture
Stress Intensity Factor
Brittle Fracture
HB (Brinell Hardness)
Thermal Shock Resistance
14. Emitted light is in phase
Coherent
Electrical Conduction
Pure Semiconductors: Conductivity vs. T
Slip Bands
15. Sigma=ln(li/lo)
Engineering Fracture Performance
Lithography
True Strain
Holloman Equation
16. Without passing a current a continually varying magnetic field will cause a current to flow
There is no perfect material?
Response to a Magnetic Field
Impact energy
Transparent
17. (sigma)=F/Ai (rho)=(rho)'(1+(epsilon))
True Stress
Ductile Materials
Not severe
How an LCD works
18. 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.
Thermal Expansion: Symmetric curve
Transparent
Coefficient of Thermal Expansion
M is known as what?
19. Transmitted light distorts electron clouds - The velocity of light in a material is lower than in a vacuum - Adding large ions to glass decreases the speed of light in the glass - Light can be "bent" (or refracted) as it passes through a transparent
Sparkle of Diamonds
Liquid Crystal Displays (LCD's)
Two kinds of Reflection
Refraction
20. Heat capacity.....- increases with temperature -for solids it reaches a limiting value of 3R
Charpy or Izod test
Intergranular Fracture
Dependence of Heat Capacity on Temperature
Modulus of Rupture (MOR)
21. 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
Griffith Crack Model
Engineering Fracture Performance
Impact - Toughness
Specific Heat
22. 1. Metals: Thermal energy puts many electrons into a higher energy state. 2. Energy States: Nearby energy states are accessible by thermal fluctuations.
Opacifiers
Thermal Stresses
Impact energy
Conduction & Electron Transport
23. Specific heat = energy input/(mass*temperature change)
Sparkle of Diamonds
Specific Heat
Thermal Stresses
Reflection of Light for Metals
24. 1. Ductility- % elongation - % reduction in area - may be of use in metal forming operations (e.g. - stretch forming). This is convenient for mechanical testing - but not very meaningful for most deformation processing. 2. Toughness- Area beneath str
How an LCD works
Pure Semiconductors: Conductivity vs. T
How to gage the extent of plastic deformation
Intrinsic Semiconductors
25. (sigma)=K(sigma)^n . K = strength coefficient - n = work hardening rate or strain hardening exponent. Large n value increases strength and hardness.
Opacifiers
Stages of Failure: Ductile Fracture
Magnetic Storage Media Types
Holloman Equation
26. Typical loading conditions are _____ enough to break all inter-atomic bonds
Not severe
True Strain
Shear and Tensile Stress
Generation of a Magnetic Field - Within a Solid Material
27. Dramatic change in impact energy is associated with a change in fracture mode from brittle to ductile.
Hardness
Ductile-to-Brittle Transition
Brittle Fracture
Generation of a Magnetic Field - Within a Solid Material
28. 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
Modulus of Rupture (MOR)
Plastic Deformation (Metals)
How an LCD works
Oxidation
29. 1. General yielding occurs if flaw size a < a(critical) 2. Catastrophic fast fracture occurs if flaw size a > a(critical)
Engineering Fracture Performance
Thermal Stresses
Rockwell
Reflection of Light for Metals
30. Small Coercivities - Used for electric motors - Example: commercial iron 99.95 Fe
Linewidth
Fourier's Law
Soft Magnetic Materials
Transparent
31. Is analogous to toughness.
The Transistor
Impact energy
Why fracture surfaces have faceted texture
Ductile Materials
32. - 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
Relative Permeability
Liquid Crystal Displays (LCD's)
Scattering
Stress Intensity values
33. Different orientation of cleavage planes in grains.
Why fracture surfaces have faceted texture
Opacifiers
Thermal Expansion: Asymmetric curve
LASER
34. The magnetic hysteresis phenomenon: Stage 1: Initial (unmagnetized state) Stage 2: Apply H - align domains Stage 3: Remove H - alignment remains => Permanent magnet Stage 4: Coercivity - Hc negative H needed to demagnitize Stage 5: Apply -H - align d
Hysteresis and Permanent Magnetization
Specific Heat
Ductile Fracture
Insulators
35. There is always some statistical distribution of flaws or defects.
Stages of Failure: Ductile Fracture
Ductile-to-Brittle Transition
There is no perfect material?
Domains in Ferromagnetic & Ferrimagnetic Materials
36. Light Amplification by Stimulated Emission of Radiation
LASER
Relative Permeability
Dependence of Heat Capacity on Temperature
Transgranular Fracture
37. Ability to transmit a clear image - The image is clear.
Large Hardness
Transparent
Slip Bands
The Transistor
38. Hardness is the resistance of a material to deformation by indentation - Useful in quality control - Hardness can provide a qualitative assessment of strength - Hardness cannot be used to quantitatively infer strength or ductility.
Impact - Toughness
Thermal Expansion: Asymmetric curve
Conduction & Electron Transport
Hardness
39. 1. Tensile (opening) 2. Sliding 3. Tearing
Two ways to measure heat capacity
Shear and Tensile Stress
Bending tests
The three modes of crack surface displacement
40. 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
Diamagnetic Materials
Thermal Stresses
Stress Intensity Factor
Electrical Conduction
41. Becomes harder (more strain) to stretch (elongate)
What do magnetic moments arise from?
Work Hardening
Magnetic Storage Media Types
Rockwell
42. Elastic means reversible! This is not a permanent deformation.
Elastic Deformation
Magnetic Storage
Two kinds of Reflection
Hysteresis and Permanent Magnetization
43. Energy is stored as atomic vibrations - As temperature increases - the average energy of atomic vibrations increases.
Ductile-to-Brittle Transition
True Strain
Intrinsic Semiconductors
Heat Capacity from an Atomic Prospective
44. Growing interconnections to connect devices -Low electrical resistance - good adhesion to dielectric insulators.
Metallization
Reflectance of Non-Metals
The Transistor
Refraction
45. Occur due to: restrained thermal expansion/contraction -temperature gradients that lead to differential dimensional changes sigma = Thermal Stress
Reflectance of Non-Metals
Thermal Stresses
Paramagnetic Materials
HB (Brinell Hardness)
46. - 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
There is no perfect material?
Luminescence
Critical Properties of Superconductive Materials
Color
47. Ohms Law: voltage drop = current * resistance
Ductile-to-Brittle Transition
Magnetic Storage Media Types
Soft Magnetic Materials
Electrical Conduction
48. Impurities added to the semiconductor that contribute to excess electrons or holes. Doping = intentional impurities.
Superconductivity
Magnetic Storage
Extrinsic Semiconductors
Thermal Expansion: Symmetric curve
49. 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)
Heat Capacity
Oxidation
Shear and Tensile Stress
Generation of a Magnetic Field - Vacuum
50. This strength parameter is similar in magnitude to a tensile strength. Fracture occurs along the outermost sample edge - which is under a tensile load.
Where does DBTT occur?
Incoherent
Modulus of Rupture (MOR)
Rockwell