SUBJECTS
|
BROWSE
|
CAREER CENTER
|
POPULAR
|
JOIN
|
LOGIN
Business Skills
|
Soft Skills
|
Basic Literacy
|
Certifications
About
|
Help
|
Privacy
|
Terms
|
Email
Search
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. Another optical property - Depends on the wavelength of the visible spectrum.
Opacity
To improve fatigue life
Energy States: Insulators and Semiconductors
Color
2. Wet: isotropic - under cut Dry: ansiotropic - directional
Modulus of Rupture (MOR)
Etching
Iron-Silicon Alloy in Transformer Cores
Stress Intensity Factor
3. They are used to assess properties of ceramics & glasses.
Electromigration
Why materials fail in service
Bending tests
Fatigue
4. To build a device - various thin metal or insulating films are grown on top of each other - Evaporation - MBE - Sputtering - CVD (ALD)
Coefficient of Thermal Expansion
Scattering
Magnetic Storage
Film Deposition
5. Rho=F/A - tau=G/A . Depending on what angle the force is applied - and what angle the crystal is at - it takes different amounts of force to induce plastic deformation.
Shear and Tensile Stress
The three modes of crack surface displacement
Ductile Fracture
Response to a Magnetic Field
6. Width of smallest feature obtainable on Si surface
IC Devices: P-N Rectifying Junction
Linewidth
M is known as what?
There is no perfect material?
7. These materials are "attracted" to magnetic fields.
Paramagnetic Materials
Luminescence
The three modes of crack surface displacement
Work Hardening
8. 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
Hard Magnetic Materials
Etching
Shear and Tensile Stress
Impact - Toughness
9. Undergo little or no plastic deformation.
Brittle Materials
Two ways to measure heat capacity
How an LCD works
Soft Magnetic Materials
10. Not ALL the light is refracted - SOME is reflected. Materials with a high index of refraction also have high reflectance - High R is bad for lens applications - since this leads to undesirable light losses or interference.
How to gage the extent of plastic deformation
Reflectance of Non-Metals
Bending tests
Refraction
11. Metals are good conductors since their _______is only partially filled.
IC Devices: P-N Rectifying Junction
4 Types of Magnetism
Superconductivity
Valence band
12. As the applied field (H) increases the magnetic domains change shape and size by movement of domain boundaries.
Not severe
Liquid Crystal Displays (LCD's)
Ductile Materials
Domains in Ferromagnetic & Ferrimagnetic Materials
13. With Increasing temperature - the saturation magnetization diminishes gradually and then abruptly drops to zero at Curie Temperature - Tc.
Magnetic Storage
Thermal expansion
Influence of Temperature on Magnetic Behavior
Yield and Reliability
14. 1. Imperfections increase resistivity - grain boundaries - dislocations - impurity atoms - vacancies 2. Resistivity - increases with temperature - wt% impurity - and %CW
Heat Capacity
LASER
Metals: Resistivity vs. T - Impurities
Coefficient of Thermal Expansion
15. 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
Generation of a Magnetic Field - Within a Solid Material
How an LCD works
Thermal Stresses
The Transistor
16. Small Coercivities - Used for electric motors - Example: commercial iron 99.95 Fe
Luminescence examples
How to gage the extent of plastic deformation
Soft Magnetic Materials
True Stress
17. 1. Diamagnetic (Xm ~ 10^-5) - small and negative magnetic susceptibilities 2. Paramagnetic (Xm ~ 10^-4) - small and positive magnetic susceptibilities 3. Ferromagnetic - large magnetic susceptibilities 4. Ferrimagnetic (Xm as large as 10^6) - large m
4 Types of Magnetism
Meissner Effect
Critical Properties of Superconductive Materials
Paramagnetic Materials
18. 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
Stages of Failure: Ductile Fracture
Thermal Expansion: Symmetric curve
To improve fatigue life
Hysteresis and Permanent Magnetization
19. Degree of opacity depends on size and number of particles - Opacity of metals is the result of conduction electrons absorbing photons in the visible range.
Color
Pure Semiconductors: Conductivity vs. T
Conduction & Electron Transport
Opacity
20. 1. Metals: Thermal energy puts many electrons into a higher energy state. 2. Energy States: Nearby energy states are accessible by thermal fluctuations.
Valence band
Fatigue
Rockwell
Conduction & Electron Transport
21. 1. Impose a compressive surface stress (to suppress surface cracks from growing) - Method 1: shot peening - Method 2: carburizing 2.Remove stress concentrators.
Slip Bands
To improve fatigue life
Iron-Silicon Alloy in Transformer Cores
Coefficient of Thermal Expansion
22. Transformer cores require soft magnetic materials - which are easily magnetized and de-magnetized - and have high electrical resistivity - Energy losses in transformers could be minimized if their cores were fabricated such that the easy magnetizatio
Magnetic Storage
Stress Intensity values
Brittle Ceramics
Iron-Silicon Alloy in Transformer Cores
23. This strength parameter is similar in magnitude to a tensile strength. Fracture occurs along the outermost sample edge - which is under a tensile load.
Coefficient of Thermal Expansion
Yield and Reliability
Modulus of Rupture (MOR)
Etching
24. Plastic means permanent! When a small load is applied - bonds stretch & planes shear. Then when the load is no longer applied - the planes are still sheared.
Impact - Toughness
True Strain
Plastic Deformation (Metals)
Coherent
25. 1. Necking 2. Cavity formation 3. Cavity coalescence to form cracks 4. Crack propagation (growth) 5. Fracture
Conduction & Electron Transport
Ductile Fracture
Luminescence examples
Stages of Failure: Ductile Fracture
26. 1. Electron motions 2. The spins on electrons - Net atomic magnetic moment: sum of moments from all electrons.
Ductile Materials
Influence of Temperature on Magnetic Behavior
Modulus of Rupture (MOR)
What do magnetic moments arise from?
27. Measures Hardness - No major sample damage - Each scales runs to 130 but only useful in range 20-100 - Minor load is 10 kg - Major load: 60 kg (diamond) - 100 kg (1/16 in. ball) - 150 kg (diamond)
Opacity
Linewidth
Force Decomposition
Rockwell
28. Diffuse image
LASER
Why materials fail in service
Translucent
Lithography
29. A measure of the ease with which a B field can be induced inside a material.
Thermal Expansion: Asymmetric curve
Internal magnetic moments
Thermal Stresses
Relative Permeability
30. 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.
Metals: Resistivity vs. T - Impurities
Heat Capacity
Sparkle of Diamonds
Intrinsic Semiconductors
31. Superconductors expel magnetic fields - This is why a superconductor will float above a magnet.
Engineering Fracture Performance
True Stress
Linewidth
Meissner Effect
32. Sigma=ln(li/lo)
Insulators
True Stress
True Strain
Color
33. Is analogous to toughness.
Two ways to measure heat capacity
Where does DBTT occur?
Impact energy
Ductile Fracture
34. There is always some statistical distribution of flaws or defects.
There is no perfect material?
Color
Hysteresis and Permanent Magnetization
Electrical Conduction
35. 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
Refraction
Fourier's Law
Heat Capacity from an Atomic Prospective
Soft Magnetic Materials
36. Is reflected - absorbed - scattered - and/or transmitted: Io=It+Ia+Ir+Is
Opaque
M is known as what?
Relative Permeability
Incident Light
37. Heat capacity.....- increases with temperature -for solids it reaches a limiting value of 3R
Hard Magnetic Materials
Dependence of Heat Capacity on Temperature
Hysteresis and Permanent Magnetization
Thermal Expansion: Symmetric curve
38. If a material has ________ - then the field generated by those moments must be added to the induced field.
Critical Properties of Superconductive Materials
Generation of a Magnetic Field - Within a Solid Material
Internal magnetic moments
Incoherent
39. High toughness; material resists crack propagation.
Work Hardening
Fatigue
Etching
High impact energy
40. A parallel-plate capacitor involves an insulator - or dielectric - between two metal electrodes. The charge density buildup at the capacitor surface is related to the dielectric constant of the material.
Insulators
Linewidth
Impact - Toughness
Iron-Silicon Alloy in Transformer Cores
41. Process by which geometric patterns are transferred from a mask (reticle) to a surface of a chip to form the device.
Lithography
Impact energy
Impact - Toughness
Charpy or Izod test
42. Increase temperature - increase in interatomic separation - thermal expansion
Luminescence
Specific Heat
Valence band
Thermal Expansion: Asymmetric curve
43. Increase temperature - no increase in interatomic separation - no thermal expansion
Reflectance of Non-Metals
Intergranular Fracture
Engineering Fracture Performance
Thermal Expansion: Symmetric curve
44. 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 to gage the extent of plastic deformation
Opaque
Yield and Reliability
Engineering Fracture Performance
45. Occur when lots of dislocations move.
Slip Bands
How an LCD works
Soft Magnetic Materials
Specific Heat
46. Ohms Law: voltage drop = current * resistance
Electrical Conduction
Critical Properties of Superconductive Materials
Hardness
Dependence of Heat Capacity on Temperature
47. The ability of a material to be rapidly cooled and not fracture
Plastic Deformation (Metals)
Thermal Shock Resistance
Critical Properties of Superconductive Materials
Dependence of Heat Capacity on Temperature
48. Allows you to calculate what happened G=F' x cos(lambda) - F=F' x cos(phi)
Force Decomposition
Energy States: Insulators and Semiconductors
Dependence of Heat Capacity on Temperature
Thermal Conductivity
49. # of thermally generated electrons = # of holes (broken bonds)
Energy States: Insulators and Semiconductors
Electromigration
LASER
Intrinsic Semiconductors
50. Occur due to: restrained thermal expansion/contraction -temperature gradients that lead to differential dimensional changes sigma = Thermal Stress
Extrinsic Semiconductors
True Strain
Hysteresis and Permanent Magnetization
Thermal Stresses