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. 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.
True Stress
Force Decomposition
Scattering
Valence band
2. 1. Data for Pure Silicon - electrical conductivity increases with T - opposite to metals
Slip Bands
Etching
Force Decomposition
Pure Semiconductors: Conductivity vs. T
3. Flaws and Defects - They concentrate stress locally to levels high enough to rupture bonds.
Modulus of Rupture (MOR)
Internal magnetic moments
LASER
Why materials fail in service
4. Growing interconnections to connect devices -Low electrical resistance - good adhesion to dielectric insulators.
Metallization
Brittle Fracture
Thermal Shock Resistance
4 Types of Magnetism
5. Increase temperature - increase in interatomic separation - thermal expansion
Thermal Expansion: Asymmetric curve
Specific Heat
Dependence of Heat Capacity on Temperature
Stress Intensity Factor
6. 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.
Thermal expansion
Shear and Tensile Stress
Reflection of Light for Metals
Brittle Ceramics
7. 1. Necking 2. Cavity formation 3. Cavity coalescence to form cracks 4. Crack propagation (growth) 5. Fracture
Stages of Failure: Ductile Fracture
Oxidation
Stress Intensity Factor
Sparkle of Diamonds
8. 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)
Shear and Tensile Stress
Two kinds of Reflection
Brittle Fracture
9. The size of the material changes with a change in temperature - polymers have the largest values
LASER
Rockwell
Lithography
Coefficient of Thermal Expansion
10. Second phase particles with n > glass.
Elastic Deformation
Force Decomposition
Metals: Resistivity vs. T - Impurities
Opacifiers
11. With Increasing temperature - the saturation magnetization diminishes gradually and then abruptly drops to zero at Curie Temperature - Tc.
Ductile-to-Brittle Transition
True Stress
Dependence of Heat Capacity on Temperature
Influence of Temperature on Magnetic Behavior
12. Cracks pass through grains - often along specific crystal planes.
Coefficient of Thermal Expansion
Thermal Stresses
Transgranular Fracture
Griffith Crack Model
13. 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.
M is known as what?
Brittle Fracture
Thermal Expansion: Asymmetric curve
Thermal Expansion: Symmetric curve
14. (sigma)=K(sigma)^n . K = strength coefficient - n = work hardening rate or strain hardening exponent. Large n value increases strength and hardness.
Holloman Equation
Domains in Ferromagnetic & Ferrimagnetic Materials
Rockwell
Brittle Fracture
15. Without passing a current a continually varying magnetic field will cause a current to flow
What do magnetic moments arise from?
Fourier's Law
Translucent
Response to a Magnetic Field
16. 1. Electron motions 2. The spins on electrons - Net atomic magnetic moment: sum of moments from all electrons.
Thermal Expansion: Asymmetric curve
What do magnetic moments arise from?
Shear and Tensile Stress
Thermal Conductivity
17. There is always some statistical distribution of flaws or defects.
Thermal Shock Resistance
There is no perfect material?
Transgranular Fracture
True Stress
18. 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.
Modulus of Rupture (MOR)
Thermal expansion
Thermal Expansion: Asymmetric curve
Insulators
19. 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)
Stress Intensity Factor
IC Devices: P-N Rectifying Junction
Transparent
20. Diffuse image
Modulus of Rupture (MOR)
Thermal Expansion: Symmetric curve
Translucent
Incident Light
21. 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: Symmetric curve
Hysteresis and Permanent Magnetization
Refraction
Linewidth
22. - 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
Stages of Failure: Ductile Fracture
Magnetic Storage Media Types
Luminescence
Response to a Magnetic Field
23. Failure under cyclic stress 1. It can cause part failure - even though (sigma)max < (sigma)c 2. Causes ~90% of mechanical engineering failures.
Generation of a Magnetic Field - Vacuum
Superconductivity
Fatigue
Incoherent
24. Ability to transmit a clear image - The image is clear.
Impact energy
Holloman Equation
Transparent
Domains in Ferromagnetic & Ferrimagnetic Materials
25. Different orientation of cleavage planes in grains.
Why fracture surfaces have faceted texture
Pure Semiconductors: Conductivity vs. T
Stress Intensity Factor
Shear and Tensile Stress
26. Cp: Heat capacity at constant pressure Cv: Heat capacity at constant volume.
Reflection of Light for Metals
Holloman Equation
Oxidation
Two ways to measure heat capacity
27. Allows flow of electrons in one direction only (useful to convert alternating current to direct current) - Result: no net current flow
Dependence of Heat Capacity on Temperature
IC Devices: P-N Rectifying Junction
Heat Capacity from an Atomic Prospective
Charpy or Izod test
28. 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
Linewidth
Two kinds of Reflection
How to gage the extent of plastic deformation
Thermal Stresses
29. 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
Ductile-to-Brittle Transition
Hysteresis and Permanent Magnetization
4 Types of Magnetism
Oxidation
30. Materials change size when temperature is changed
Thermal Conductivity
Energy States: Insulators and Semiconductors
Thermal expansion
Magnetic Storage Media Types
31. 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
Energy States: Insulators and Semiconductors
Stress Intensity Factor
Force Decomposition
Bending tests
32. Undergo extensive plastic deformation prior to failure.
Ductile Materials
Two kinds of Reflection
Large Hardness
Sparkle of Diamonds
33. Measures Hardness 1. psia = 500 x HB 2. MPa = 3.45 x HB
HB (Brinell Hardness)
Conduction & Electron Transport
Opacity
Generation of a Magnetic Field - Vacuum
34. 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
Refraction
Charpy or Izod test
Extrinsic Semiconductors
4 Types of Magnetism
35. Found in 26 metals and hundreds of alloys & compounds - Tc= critical temperature = termperature below which material is superconductive.
Ductile-to-Brittle Transition
Liquid Crystal Displays (LCD's)
Superconductivity
Luminescence examples
36. 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.
Stages of Failure: Ductile Fracture
Opaque
There is no perfect material?
Why fracture surfaces have faceted texture
37. ...occurs in bcc metals but not in fcc metals.
Refraction
Brittle Ceramics
Impact energy
Where does DBTT occur?
38. 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
Reflection of Light for Metals
Bending tests
Ductile-to-Brittle Transition
Magnetic Storage
39. Occur when lots of dislocations move.
Fatigue
Sparkle of Diamonds
IC Devices: P-N Rectifying Junction
Slip Bands
40. Wet: isotropic - under cut Dry: ansiotropic - directional
Etching
Work Hardening
Elastic Deformation
Superconductivity
41. Is reflected - absorbed - scattered - and/or transmitted: Io=It+Ia+Ir+Is
Incident Light
Refraction
Domains in Ferromagnetic & Ferrimagnetic Materials
Why fracture surfaces have faceted texture
42. Another optical property - Depends on the wavelength of the visible spectrum.
Electrical Conduction
Generation of a Magnetic Field - Within a Solid Material
Why materials fail in service
Color
43. Becomes harder (more strain) to stretch (elongate)
Thermal Expansion: Symmetric curve
Heat Capacity
Work Hardening
Film Deposition
44. Light Amplification by Stimulated Emission of Radiation
To improve fatigue life
Incident Light
Linewidth
LASER
45. Sigma=ln(li/lo)
Critical Properties of Superconductive Materials
Not severe
True Strain
Transparent
46. # of thermally generated electrons = # of holes (broken bonds)
Thermal Conductivity
Etching
LASER
Intrinsic Semiconductors
47. Allows you to calculate what happened G=F' x cos(lambda) - F=F' x cos(phi)
Force Decomposition
Impact energy
Metallization
Stress Intensity Factor
48. Elastic means reversible! This is not a permanent deformation.
Opacifiers
Reflectance of Non-Metals
Elastic Deformation
Thermal Stresses
49. 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)
Rockwell
Intergranular Fracture
Impact - Toughness
Incoherent
50. Process by which metal atoms diffuse because of a potential.
Luminescence examples
Intergranular Fracture
Influence of Temperature on Magnetic Behavior
Electromigration