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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. - 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
Plastic Deformation (Metals)
Opaque
Why fracture surfaces have faceted texture
2. Ability to transmit a clear image - The image is clear.
Transparent
Relative Permeability
IC Devices: P-N Rectifying Junction
Impact energy
3. Impurities added to the semiconductor that contribute to excess electrons or holes. Doping = intentional impurities.
Brittle Materials
Fatigue
Ductile Materials
Extrinsic Semiconductors
4. Large coercivities - Used for permanent magnets - Add particles/voids to inhibit domain wall motion - Example: tungsten steel
Energy States: Insulators and Semiconductors
Hard Magnetic Materials
Scattering
Refraction
5. 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
Iron-Silicon Alloy in Transformer Cores
Why do ceramics have larger bonding energy?
Reflection of Light for Metals
6. Resistance to plastic deformation of cracking in compression - and better wear properties.
Valence band
Extrinsic Semiconductors
M is known as what?
Large Hardness
7. High toughness; material resists crack propagation.
Coherent
High impact energy
Modulus of Rupture (MOR)
The Transistor
8. Energy is stored as atomic vibrations - As temperature increases - the average energy of atomic vibrations increases.
Specific Heat
Heat Capacity from an Atomic Prospective
Thermal expansion
Plastic Deformation (Metals)
9. To build a device - various thin metal or insulating films are grown on top of each other - Evaporation - MBE - Sputtering - CVD (ALD)
Ductile-to-Brittle Transition
IC Devices: P-N Rectifying Junction
Brittle Materials
Film Deposition
10. Measures Hardness 1. psia = 500 x HB 2. MPa = 3.45 x HB
HB (Brinell Hardness)
Bending tests
Soft Magnetic Materials
Relative Permeability
11. A high index of refraction (n value) allows for multiple internal reactions.
Thermal Expansion: Symmetric curve
Impact - Toughness
Sparkle of Diamonds
Thermal Stresses
12. Loss of image transmission - You get no image - There is no light transmission - and therefore reflects - scatters - or absorbs ALL of it. Both mirrors and carbon black are opaque.
Not severe
M is known as what?
Opaque
Why do ceramics have larger bonding energy?
13. 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
Reflectance of Non-Metals
Thermal Conductivity
Sparkle of Diamonds
Refraction
14. Specular: light reflecting off a mirror (average) - Diffuse: light reflecting off a white wall (local)
Domains in Ferromagnetic & Ferrimagnetic Materials
Two kinds of Reflection
Conduction & Electron Transport
Generation of a Magnetic Field - Within a Solid Material
15. Different orientation of cleavage planes in grains.
Generation of a Magnetic Field - Within a Solid Material
Luminescence examples
Yield and Reliability
Why fracture surfaces have faceted texture
16. Stress concentration at a crack tips
Opaque
Thermal Expansion: Symmetric curve
Superconductivity
Griffith Crack Model
17. For a metal - there is no ______ - only reflection
Opacity
Refraction
Reflection of Light for Metals
Thermal Expansion: Asymmetric curve
18. This strength parameter is similar in magnitude to a tensile strength. Fracture occurs along the outermost sample edge - which is under a tensile load.
Modulus of Rupture (MOR)
Valence band
Internal magnetic moments
Linewidth
19. Is reflected - absorbed - scattered - and/or transmitted: Io=It+Ia+Ir+Is
Electromigration
Extrinsic Semiconductors
What do magnetic moments arise from?
Incident Light
20. (sigma)=F/Ai (rho)=(rho)'(1+(epsilon))
Opaque
Refraction
M is known as what?
True Stress
21. 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
Impact energy
Critical Properties of Superconductive Materials
Thermal Conductivity
Pure Semiconductors: Conductivity vs. T
22. 1. Stress-strain behavior is not usually determined via tensile tests 2. Material fails before it yields 3. Bend/flexure tests are often used instead.
Fourier's Law
Domains in Ferromagnetic & Ferrimagnetic Materials
Coherent
Brittle Ceramics
23. The ability of a material to be rapidly cooled and not fracture
Thermal Shock Resistance
Holloman Equation
Elastic Deformation
Thermal Stresses
24. As the applied field (H) increases the magnetic domains change shape and size by movement of domain boundaries.
Domains in Ferromagnetic & Ferrimagnetic Materials
Oxidation
Translucent
Modulus of Rupture (MOR)
25. 1. General yielding occurs if flaw size a < a(critical) 2. Catastrophic fast fracture occurs if flaw size a > a(critical)
Critical Properties of Superconductive Materials
Why fracture surfaces have faceted texture
Engineering Fracture Performance
Thermal Conductivity
26. 1. Impose a compressive surface stress (to suppress surface cracks from growing) - Method 1: shot peening - Method 2: carburizing 2.Remove stress concentrators.
LASER
Etching
To improve fatigue life
The three modes of crack surface displacement
27. Without passing a current a continually varying magnetic field will cause a current to flow
Impact - Toughness
Domains in Ferromagnetic & Ferrimagnetic Materials
Response to a Magnetic Field
Work Hardening
28. 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.
Yield and Reliability
Impact energy
Shear and Tensile Stress
Impact - Toughness
29. 1. Metals: Thermal energy puts many electrons into a higher energy state. 2. Energy States: Nearby energy states are accessible by thermal fluctuations.
Conduction & Electron Transport
Holloman Equation
Relative Permeability
Two ways to measure heat capacity
30. Heat capacity.....- increases with temperature -for solids it reaches a limiting value of 3R
Dependence of Heat Capacity on Temperature
IC Devices: P-N Rectifying Junction
Lithography
Opacifiers
31. 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
Relative Permeability
Thermal Stresses
Fatigue
32. No appreciable plastic deformation. The crack propagates very fast; nearly perpendicular to applied stress. Cracks often propagate along specific crystal planes or boundaries.
Where does DBTT occur?
Brittle Fracture
Engineering Fracture Performance
Soft Magnetic Materials
33. 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
Translucent
Relative Permeability
Oxidation
How an LCD works
34. 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
Holloman Equation
Stress Intensity Factor
Oxidation
Luminescence examples
35. Process by which metal atoms diffuse because of a potential.
To improve fatigue life
Incident Light
Electromigration
Etching
36. Undergo little or no plastic deformation.
Refraction
Ductile-to-Brittle Transition
Brittle Materials
Stages of Failure: Ductile Fracture
37. Digitalized data in the form of electrical signals are transferred to and recorded digitally on a magnetic medium (tape or disk) - This transference is accomplished by a recording system that consists of a read/write head - "write" or record data by
Transparent
Electrical Conduction
Magnetic Storage
Response to a Magnetic Field
38. 1. Electron motions 2. The spins on electrons - Net atomic magnetic moment: sum of moments from all electrons.
Scattering
Hard Magnetic Materials
Ductile Materials
What do magnetic moments arise from?
39. Emitted light is in phase
Reflectance of Non-Metals
Magnetic Storage Media Types
M is known as what?
Coherent
40. 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
Impact - Toughness
Scattering
Ductile Materials
Metals: Resistivity vs. T - Impurities
41. (sigma)=K(sigma)^n . K = strength coefficient - n = work hardening rate or strain hardening exponent. Large n value increases strength and hardness.
Coefficient of Thermal Expansion
IC Devices: P-N Rectifying Junction
HB (Brinell Hardness)
Holloman Equation
42. 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
Dependence of Heat Capacity on Temperature
Opacity
Oxidation
Why fracture surfaces have faceted texture
43. 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."
What do magnetic moments arise from?
HB (Brinell Hardness)
Charpy or Izod test
Yield and Reliability
44. - A magnetic field is induced in the material B= Magnetic Induction (tesla) inside the material mu= permeability of a solid
Where does DBTT occur?
Generation of a Magnetic Field - Within a Solid Material
Incident Light
Bending tests
45. 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.
Refraction
Thermal Expansion: Asymmetric curve
Luminescence examples
The Transistor
46. Cracks pass through grains - often along specific crystal planes.
Metallization
Etching
Transgranular Fracture
Opaque
47. -> fluorescent light - electron transitions occur randomly - light waves are out of phase with each other.
Incoherent
Stress Intensity values
Griffith Crack Model
Etching
48. Specific heat = energy input/(mass*temperature change)
Incident Light
Specific Heat
Brittle Materials
How to gage the extent of plastic deformation
49. They are used to assess properties of ceramics & glasses.
Insulators
Bending tests
Ductile Fracture
Stress Intensity Factor
50. 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
Lithography
Yield and Reliability
Color
The three modes of crack surface displacement