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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. Specific heat = energy input/(mass*temperature change)
True Stress
Coherent
Color
Specific Heat
2. Cp: Heat capacity at constant pressure Cv: Heat capacity at constant volume.
Opacity
Modulus of Rupture (MOR)
Two ways to measure heat capacity
Hysteresis and Permanent Magnetization
3. Heat capacity.....- increases with temperature -for solids it reaches a limiting value of 3R
Heat Capacity from an Atomic Prospective
Coherent
Coefficient of Thermal Expansion
Dependence of Heat Capacity on Temperature
4. 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.
Internal magnetic moments
Iron-Silicon Alloy in Transformer Cores
Scattering
Insulators
5. 1. Tensile (opening) 2. Sliding 3. Tearing
Brittle Ceramics
Paramagnetic Materials
Ductile Fracture
The three modes of crack surface displacement
6. Impurities added to the semiconductor that contribute to excess electrons or holes. Doping = intentional impurities.
Extrinsic Semiconductors
Modulus of Rupture (MOR)
Energy States: Insulators and Semiconductors
Etching
7. Stress concentration at a crack tips
Specific Heat
Griffith Crack Model
Stress Intensity Factor
Opacity
8. Energy is stored as atomic vibrations - As temperature increases - the average energy of atomic vibrations increases.
Oxidation
Luminescence examples
Heat Capacity from an Atomic Prospective
Intergranular Fracture
9. 1. Electron motions 2. The spins on electrons - Net atomic magnetic moment: sum of moments from all electrons.
Not severe
Electrical Conduction
Metals: Resistivity vs. T - Impurities
What do magnetic moments arise from?
10. These materials are "attracted" to magnetic fields.
Magnetic Storage
Paramagnetic Materials
Incoherent
Reflectance of Non-Metals
11. 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.
Plastic Deformation (Metals)
Scattering
Insulators
4 Types of Magnetism
12. Typical loading conditions are _____ enough to break all inter-atomic bonds
Not severe
Opacifiers
Thermal Expansion: Asymmetric curve
Bending tests
13. A measure of the ease with which a B field can be induced inside a material.
Relative Permeability
Paramagnetic Materials
Rockwell
Yield and Reliability
14. # of thermally generated electrons = # of holes (broken bonds)
Soft Magnetic Materials
Why materials fail in service
Intrinsic Semiconductors
True Stress
15. 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
Transparent
Soft Magnetic Materials
Opacity
Stress Intensity Factor
16. Materials change size when temperature is changed
Thermal expansion
Etching
Meissner Effect
Brittle Materials
17. The ability of a material to transport heat - Atomic Perspective: Atomic vibrations and free electrons in hotter regions transport energy to cooler regions - Metals have the largest values
Thermal Conductivity
Transparent
Why fracture surfaces have faceted texture
Translucent
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 Shock Resistance
M is known as what?
Critical Properties of Superconductive Materials
IC Devices: P-N Rectifying Junction
19. Wet: isotropic - under cut Dry: ansiotropic - directional
Etching
Conduction & Electron Transport
Color
To improve fatigue life
20. 1. Insulators: Higher energy states NOT ACCESSIBLE due to gap 2. Semiconductors: Higher energy states separated by a smaller gap.
How an LCD works
Energy States: Insulators and Semiconductors
Valence band
Meissner Effect
21. Resistance to plastic deformation of cracking in compression - and better wear properties.
Large Hardness
Luminescence examples
Opacifiers
Electrical Conduction
22. Large coercivities - Used for permanent magnets - Add particles/voids to inhibit domain wall motion - Example: tungsten steel
Thermal Expansion: Symmetric curve
Hard Magnetic Materials
Brittle Materials
Brittle Ceramics
23. Is analogous to toughness.
LASER
Scattering
Response to a Magnetic Field
Impact energy
24. 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)
Thermal Shock Resistance
Large Hardness
Shear and Tensile Stress
Rockwell
25. 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
Critical Properties of Superconductive Materials
Energy States: Insulators and Semiconductors
Sparkle of Diamonds
Metals: Resistivity vs. T - Impurities
26. As the applied field (H) increases the magnetic domains change shape and size by movement of domain boundaries.
Domains in Ferromagnetic & Ferrimagnetic Materials
Metallization
LASER
Generation of a Magnetic Field - Within a Solid Material
27. Dimples on fracture surface correspond to microcavities that initiate crack formation.
Metals: Resistivity vs. T - Impurities
Rockwell
Ductile Fracture
Intrinsic Semiconductors
28. This strength parameter is similar in magnitude to a tensile strength. Fracture occurs along the outermost sample edge - which is under a tensile load.
Why fracture surfaces have faceted texture
Refraction
Brittle Ceramics
Modulus of Rupture (MOR)
29. 1. Yield = ratio of functional chips to total # of chips - Most yield loss during wafer processing - b/c of complex 2. Reliability - No device has infinite lifetime. Statistical methods to predict expected lifetime - Failure mechanisms: Diffusion reg
Yield and Reliability
Reflection of Light for Metals
Response to a Magnetic Field
How an LCD works
30. Metals are good conductors since their _______is only partially filled.
Yield and Reliability
Stages of Failure: Ductile Fracture
Opacity
Valence band
31. Growing interconnections to connect devices -Low electrical resistance - good adhesion to dielectric insulators.
Domains in Ferromagnetic & Ferrimagnetic Materials
Metallization
Holloman Equation
IC Devices: P-N Rectifying Junction
32. Cracks pass through grains - often along specific crystal planes.
Transgranular Fracture
Opacifiers
Intrinsic Semiconductors
Impact - Toughness
33. With Increasing temperature - the saturation magnetization diminishes gradually and then abruptly drops to zero at Curie Temperature - Tc.
Domains in Ferromagnetic & Ferrimagnetic Materials
Heat Capacity from an Atomic Prospective
Influence of Temperature on Magnetic Behavior
True Stress
34. Width of smallest feature obtainable on Si surface
Why materials fail in service
There is no perfect material?
Linewidth
Heat Capacity from an Atomic Prospective
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
Thermal Expansion: Asymmetric curve
Magnetic Storage Media Types
Refraction
Holloman Equation
36. 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.
Opaque
The Transistor
Insulators
Incoherent
37. If a material has ________ - then the field generated by those moments must be added to the induced field.
Liquid Crystal Displays (LCD's)
HB (Brinell Hardness)
Internal magnetic moments
Dependence of Heat Capacity on Temperature
38. Superconductors expel magnetic fields - This is why a superconductor will float above a magnet.
Paramagnetic Materials
Meissner Effect
Magnetic Storage
Luminescence
39. - 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
Luminescence
Work Hardening
Opacity
Why fracture surfaces have faceted texture
40. High toughness; material resists crack propagation.
Paramagnetic Materials
Thermal Shock Resistance
Not severe
High impact energy
41. Without passing a current a continually varying magnetic field will cause a current to flow
Response to a Magnetic Field
Meissner Effect
Incoherent
Charpy or Izod test
42. Becomes harder (more strain) to stretch (elongate)
Insulators
Work Hardening
Stages of Failure: Ductile Fracture
Impact - Toughness
43. 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.
Opacity
Why materials fail in service
Bending tests
Relative Permeability
44. Process by which geometric patterns are transferred from a mask (reticle) to a surface of a chip to form the device.
Modulus of Rupture (MOR)
Lithography
Scattering
Brittle Fracture
45. 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
Thermal Expansion: Asymmetric curve
Hysteresis and Permanent Magnetization
Thermal Expansion: Symmetric curve
Refraction
46. (sigma)=F/Ai (rho)=(rho)'(1+(epsilon))
Rockwell
True Stress
Transparent
Why fracture surfaces have faceted texture
47. To build a device - various thin metal or insulating films are grown on top of each other - Evaporation - MBE - Sputtering - CVD (ALD)
Magnetic Storage Media Types
Plastic Deformation (Metals)
Incident Light
Film Deposition
48. The size of the material changes with a change in temperature - polymers have the largest values
Coefficient of Thermal Expansion
High impact energy
Fatigue
Influence of Temperature on Magnetic Behavior
49. The ability of a material to be rapidly cooled and not fracture
Stages of Failure: Ductile Fracture
Yield and Reliability
Brittle Ceramics
Thermal Shock Resistance
50. Occur when lots of dislocations move.
Domains in Ferromagnetic & Ferrimagnetic Materials
Stress Intensity values
Linewidth
Slip Bands