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. Energy is stored as atomic vibrations - As temperature increases - the average energy of atomic vibrations increases.
Coherent
Heat Capacity from an Atomic Prospective
Refraction
Fourier's Law
2. Becomes harder (more strain) to stretch (elongate)
Magnetic Storage
Coherent
Electrical Conduction
Work Hardening
3. 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.
Large Hardness
Reflectance of Non-Metals
Elastic Deformation
Translucent
4. Increase temperature - increase in interatomic separation - thermal expansion
Where does DBTT occur?
Soft Magnetic Materials
Griffith Crack Model
Thermal Expansion: Asymmetric curve
5. These are liquid crystal polymers- not your normal "crystal" -Rigid - rod shaped molecules are aligned even in liquid form.
Warning
: Invalid argument supplied for foreach() in
/var/www/html/basicversity.com/show_quiz.php
on line
183
6. Width of smallest feature obtainable on Si surface
Linewidth
Incoherent
Color
Holloman Equation
7. Large coercivities - Used for permanent magnets - Add particles/voids to inhibit domain wall motion - Example: tungsten steel
Charpy or Izod test
Why materials fail in service
Diamagnetic Materials
Hard Magnetic Materials
8. Undergo little or no plastic deformation.
Ductile-to-Brittle Transition
Why materials fail in service
Brittle Materials
Color
9. Undergo extensive plastic deformation prior to failure.
Ductile Materials
True Stress
IC Devices: P-N Rectifying Junction
Work Hardening
10. 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)
Linewidth
Rockwell
The Transistor
Modulus of Rupture (MOR)
11. 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.
Brittle Ceramics
The Transistor
Etching
Hysteresis and Permanent Magnetization
12. Ohms Law: voltage drop = current * resistance
Electrical Conduction
Holloman Equation
Charpy or Izod test
Fatigue
13. Reflectiviy is between 0.90 and 0.95 - Metal surfaces appear shiny - Most of absorbed light is reflected at the same wavelength (NO REFRACTION) - Small fraction of light may be absorbed - Color of reflected light depends on wavelength distribution of
Coefficient of Thermal Expansion
Reflection of Light for Metals
Luminescence examples
Oxidation
14. 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.
Slip Bands
Shear and Tensile Stress
Impact energy
Opacity
15. Second phase particles with n > glass.
Transgranular Fracture
The three modes of crack surface displacement
Opacifiers
Film Deposition
16. 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
Opaque
Dependence of Heat Capacity on Temperature
Charpy or Izod test
17. Stress concentration at a crack tips
Specific Heat
Griffith Crack Model
Fatigue
Magnetic Storage Media Types
18. 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.
Fatigue
Magnetic Storage
Opaque
Reflectance of Non-Metals
19. 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
The Transistor
Impact energy
Ductile Materials
Soft Magnetic Materials
20. Flaws and Defects - They concentrate stress locally to levels high enough to rupture bonds.
Why materials fail in service
How an LCD works
Engineering Fracture Performance
Influence of Temperature on Magnetic Behavior
21. Occur when lots of dislocations move.
Sparkle of Diamonds
Fatigue
Internal magnetic moments
Slip Bands
22. ...occurs in bcc metals but not in fcc metals.
Opacifiers
Sparkle of Diamonds
Thermal Conductivity
Where does DBTT occur?
23. Failure under cyclic stress 1. It can cause part failure - even though (sigma)max < (sigma)c 2. Causes ~90% of mechanical engineering failures.
Opacifiers
Fatigue
Ductile Fracture
Generation of a Magnetic Field - Within a Solid Material
24. 1. Hard disk drives (granular/perpendicular media) 2. Recording tape (particulate media)
Luminescence
Brittle Fracture
Magnetic Storage Media Types
Soft Magnetic Materials
25. These materials are "attracted" to magnetic fields.
Ductile Fracture
Stress Intensity values
Thermal expansion
Paramagnetic Materials
26. 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
Translucent
Griffith Crack Model
Oxidation
Thermal Shock Resistance
27. 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
Fourier's Law
High impact energy
Brittle Materials
28. 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
Impact energy
Etching
To improve fatigue life
Yield and Reliability
29. High toughness; material resists crack propagation.
IC Devices: P-N Rectifying Junction
High impact energy
Why fracture surfaces have faceted texture
Hardness
30. 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
Ductile Materials
4 Types of Magnetism
Force Decomposition
31. 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
How an LCD works
Impact energy
Generation of a Magnetic Field - Within a Solid Material
Impact - Toughness
32. Another optical property - Depends on the wavelength of the visible spectrum.
Large Hardness
Intrinsic Semiconductors
Iron-Silicon Alloy in Transformer Cores
Color
33. The size of the material changes with a change in temperature - polymers have the largest values
Coefficient of Thermal Expansion
Transgranular Fracture
Generation of a Magnetic Field - Vacuum
Why materials fail in service
34. 1. Electron motions 2. The spins on electrons - Net atomic magnetic moment: sum of moments from all electrons.
What do magnetic moments arise from?
Hysteresis and Permanent Magnetization
Response to a Magnetic Field
Reflectance of Non-Metals
35. Occur due to: restrained thermal expansion/contraction -temperature gradients that lead to differential dimensional changes sigma = Thermal Stress
Magnetic Storage
Thermal Stresses
Electromigration
Domains in Ferromagnetic & Ferrimagnetic Materials
36. Typical loading conditions are _____ enough to break all inter-atomic bonds
Paramagnetic Materials
Electromigration
Not severe
Domains in Ferromagnetic & Ferrimagnetic Materials
37. 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
Hysteresis and Permanent Magnetization
Iron-Silicon Alloy in Transformer Cores
Oxidation
Liquid Crystal Displays (LCD's)
38. A high index of refraction (n value) allows for multiple internal reactions.
Transparent
Sparkle of Diamonds
Engineering Fracture Performance
Fatigue
39. A measure of the ease with which a B field can be induced inside a material.
Ductile Materials
Linewidth
Why materials fail in service
Relative Permeability
40. Resistance to plastic deformation of cracking in compression - and better wear properties.
Response to a Magnetic Field
Impact energy
Force Decomposition
Large Hardness
41. 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."
Charpy or Izod test
Impact energy
Where does DBTT occur?
Two ways to measure heat capacity
42. Materials change size when temperature is changed
Thermal Stresses
Thermal expansion
Meissner Effect
Extrinsic Semiconductors
43. heat flux = -(thermal conductivity)(temperature gradient) - Defines heat transfer by CONDUCTION
Warning
: Invalid argument supplied for foreach() in
/var/www/html/basicversity.com/show_quiz.php
on line
183
44. Diffuse image
Thermal expansion
Hardness
Translucent
Intergranular Fracture
45. They are used to assess properties of ceramics & glasses.
Bending tests
Force Decomposition
Electromigration
Opaque
46. 1. Tensile (opening) 2. Sliding 3. Tearing
Specific Heat
The three modes of crack surface displacement
Impact - Toughness
Superconductivity
47. 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
Thermal Conductivity
Coherent
Magnetic Storage
Response to a Magnetic Field
48. Specific heat = energy input/(mass*temperature change)
Diamagnetic Materials
There is no perfect material?
Specific Heat
Rockwell
49. Elastic means reversible! This is not a permanent deformation.
Etching
Pure Semiconductors: Conductivity vs. T
Elastic Deformation
Fatigue
50. Cp: Heat capacity at constant pressure Cv: Heat capacity at constant volume.
Opacity
Film Deposition
True Stress
Two ways to measure heat capacity