Final Exam Metallurgy
The composition of the primary ferrite that forms in a .4% C steel is: A. 6.67% C B. 2.11% C C. .77% C D. .02% C
.02% C
We can estimate the temperature where diffusion becomes significant as: A. The melting point of the material B. 1000 Centigrade C. .4 times the melting point in absolute temp. D. .2 times the melting point when expressed in Centigrade
.2 times the melting point when expressed in Centigrade
The carbon content of a 4320 steel is about: A. .2% C B. 2.0% C C. .43% C D. 4.3% C
.2% C
The composition of pearlite is always: A. 6.67% B. 2.11% C. .77% D. .02%
.77%
The approximate amount of pearlite in a slow- cooled .4% C steel would be approximately: A. 25% B. 50% C. 75% D. 100%
50%
The approximate amount of primary ferrite in a .40% C steel (under equilibrium conditions) would be: A. 25% B. 50% C. 75% D. 100%
50%
If a steel has a Ductile-to-Brittle Transition Temperature (DBTT), it is best if it is used A. above this temperature B. Below this temperature
Above this temperature
The high hardness of ceramic materials make them excellent candidate materials for use as: A. Refractories B. Electrical and magnetic components C. Whiteware D. Abrasives
Abrasives
For aluminum alloys, the highest strength is achieved through: A. Grain size control B. Cold working C. Age hardening D. Solid solution strengthening
Age hardening
For the most effective dispersion strengthening, the dispersed second phase should be: A. Discontinuous B. Strong and hard C. Many small particles D. All of A, B and C. E. None of A, B and C
All of A, B and C
Among the quenchants of brine, water, and oil, the fastest cooling would be expected in: A. Oil B. Water C. Brine (salt water)
Brine (salt water)
Which of the following is NOT a characteristic property of ceramic materials? A. Good corrosion resistance and chemical stability B. High melting temperature C. Hard and rigid, but brittle D. Good electrical and thermal conductivity
Good electrical and thermal conductivity
Which of the following is NOT an attractive asset of aluminum and aluminum alloys? A. Easy to fabricate B. Very ductile C. Good electrical and thermal activity D. Good strength at elevated temperature
Good strength at elevated temperature
Superplastic behavior is a result of which deformation mechanism? A. Dislocation multiplication B. Grain boundary sliding C. Cross-slip of dislocations D. Localized melting
Grain boundary sliding
Compacted graphite cast iron has a structure and properties that fall between is: A. Malleable and ductile B. Gray and ductile C. White and Malleable D. Gray and white
Gray and ductile
If we were to add 5% nickel to pure copper to produce a copper-5% nickel alloy, the ductility of the alloy would be ___ the strength of pure copper. A. Greater than B. The same as C. Less than
Greater than
The crystal structure that contains close-packed planes stacked in the ABABAB sequence is: A. SC B. BCC C. FCC D. HCP
HCP
The Jominy test is used to evaluate the ____ of a steel. A. Ductility B. Hardness C. Hardenability
Hardenability
This type of test is the quickest and least expensive to conduct, and is frequently used as a quality control check during manufacturing operations. A. Tensile B. Impact C. Fatigue D. Creep E. Hardness
Hardness
Which of the following is NOT a correct statement regarding magnesium? A. Has a wide range of mechanical properties since it responds well to strengthening B. Has good machining characteristics, but the chips can burn C. Like aluminum, is poor in wear, creep and fatigue D. Has the HCP crystal structure and is characteristically brittle
Has a wide range of mechanical properties since it responds well to strengthening
Compared to materials with other structures, materials with the BCC structure tend to: A. Have greater strength B. Have greater ductility C. Be brittle
Have greater strength
This type of crystalline defect is responsible for solid solution strengthening: A. Substitutional or interstitial point defects B. Grain boundaries C. Dislocations
Substitutional or interstitial point defects
If we increase the temperature of a tensile test specimen we would expect ___ to increase. A. Yield strength B. Tensile strength C. Elastic modulus D. Reduction in area
Tensile strength
In a two-phase region of an equilibrium phase diagram, the lever law can be used to compute: A. The time required to solidify B. The yield strength of the alloy C. The chemistry of each of the phases D. The amounts of each of the phases
The amounts of each of the phases
If we cool a eutectiod composition steel (.77% C) under near-equilibrium conditions, the resulting microstructure will be: A. 100% pearlite B. 50% pearlite and 50% ferrite C. 75% pearlite and 25% ferrite D. 100% ferrite
100% pearlite
The coordination number for a structure that contains close-packed planes is: A. 6 B. 8 C. 12 D. 14
12
In order to be considered as a true stainless steel, an iron-based metal must contain more than: A. .77% B. 12% nickel C. 12% chrome D. 12% silicone
12% chrome
A shorthand notation for all cube edges in cubic crystals would be: A. <100> B. <110> C. <111> D. <123>
<100>
The close-packed directions in FCC crystals have the Miller Indices form of: A. <100> B. <110> C. <111> D. <000>
<110>
Tool steels are designated by: A. a letter-number combination where the letter indicated "family" B. a four-digit AISI-SAE number based on chemistry and carbon content
A letter-number combination where the letter indicated "family"
Primary ferrite forms when we cool between this temperature line and the A1. A. A1 B. A2 C. A3 D. Acm
A3
The corrosion resistance of copper and nickel is: A. An inherent property of the metal B. Due to an adherent oxide
An inherent property of the metal
The crystal structures of ceramic materials are often quite complex because: A. Atoms of different sizes are in the same structure B. Covalent structures often have a limited number of nearest neighbors C. Charge neutrality must be maintained throughout ionic structures D. All of the above
All of the above
When welding metals, the once-molten-metal region (fusion zone) of a weld can experience which of the following problems? A. Shrinkage problems B. Gas porosity C. Columnar crystals D. All of the above
All of the above
When a design engineer defines requirements, these requirements are: A. Mechanical properties B. Manufacturing requirements C. Geometric requirements D. All of these are design requirements
All of these are design requirements
A steel with a AISI-SAE designation of 4320 is a: A. Plain-carbon steel B. Alloy steel
Alloy steel
The surface treatment known as carburizing a material, such as a gear, is an example of a(n): A. Altered surface chemistry B. Single chemistry - dual heat treatment
Altered surface chemistry
The corrosion resistance of aluminum and titanium alloys can be attributed to: A. Low chemical reactivity of the metal itself B. An adherent, protective oxide film
An adherent, protective oxide film
The "critical cooling rate" is the slowest cooling that will produce: A. An all martensite structure B. An all pearlite structure C. Retained austenite
An all martensite structure
A substitutional point defect is: A. An atom missing from a lattice point B. An atom of one species occupying a lattice point in a lattice of another species C. An atom that is inserted into a crystal at a location that is not a lattice point.
An atom of one species occupying a lattice point in a lattice of another species
When the elastic-to-plastic transition is not distinct, we often define and agree on: A. A strain-hardening exponent B. The ultimate tensile strength C. An offset yield strength D. The breaking strength
An offset yield strength
The properties of cold worked components are usually: A. Anisotropic B. Isotropic
Anisotropic
Which of the following is NOT a correct statement about cold working? A. We can strengthen the material while producing the desired shape B. Anisotropy and residual stresses are always detrimental C. Dimensional tolerances and surface finish tent to be good D. Ductility, electrical conductivity, and corrosion resistance decrease
Anisotropy and residual stresses are always detrimental
Metals might be annealed to accomplish which of these? A. Increase ductility B. Improve conductivity C. Relieve residual stresses D. Any of these
Any of these
In this isothermal heat treatment, austenite is transformed below the nose of the T-T-T diagram to produce bainite: A. Isothermal anneal B. Austempering
Austempering
The elevated temperature (FCC) form of iron that can contain up to 2.11% carbon in solid solution is called: A. Ferrite B. O-Ferrite C. Austenite D. Cementite
Austenite
Quench cracking is a distinct possibility when rapidly cooling steels because the cooling is non-uniform (surfaces cool faster than interiors) and: A. Austenite contracts when it transforms to martensite B. Austenite expands when it transforms to martensite
Austenite expands when it transforms to martensite
The term "degree of polymerization" describes the: A. Average number of mers per molecule B. Number of different types of mers in a polymer C. Number of places other units can attach to a mer
Average number of mers per molecule
The crystal structure of martensite: A. FCC B. BCC C. BCT-- a distorted BCC where T= tetragonal
BCT
The microstructure that forms below the "nose", but above Ms in a eutectoid steel T-T-T diagram is: A. Pearlite B. Bainite C. Martensite
Bainite
This lightweight metal is unique in being lighter than aluminum, but stiffer than steel. Unfortunately it is also brittle in room temperature and the oxide is considered to be toxic. A. Nickel B. Beryllium C. Magnesium D. Titanium
Beryllium
The density of titanium is: A. Higher than steel B. Between steel and aluminum C. Lower than aluminum
Between steel and aluminum
We can promote the process of solidification by: A. Cooling further below the melting temp B. Providing nucleating surfaces C. Both A and B D. Neither A nor B
Both A and B
This structural feature is unique to dispersion strengthening. A. Substitutional point defects B. Boundaries between two different phases C. Grain boundaries D. Dislocation multiplication
Boundaries between two different phases
The H-14 suffix in 3003-H14 provides information relating to: A. Purity B. Alloying elements C. Carbon content D. Condition (past processing history)
Condition (past processing history)
During quenching, the most rapid cooling occurs during the ___ stage. A. Vapor jacket B. Bubble formation & removal C. Conduction & convection
Bubble formation & removal
The cooling conditions experienced by parts undergoing actual cooling are most accurately reflected in the: A. Equilibrium phase diagram B. T-T-T diagram C. C-T-T diagram
C-T-T diagram
The refractory metals usually have some form of protective coating. This coating is a : A. ceramic B. Polymer C. Titanium alloy D. Copper alloy
Ceramic
Materials in this family are hard or strong, offer good electrical and thermal insulation, and can be attractive for elevated temperature applications. Unfortunately, they are generally brittle. A. Metals B. Ceramics C. Polymers
Ceramics
In this region of a casting, typically the first region to solidify, many small grains form due to rapid nucleation on the walls of the mold: A. Chill B. Columnar C. Equiaxed D. Heat affected
Chill
This region of casting results from the selective growth of already- existing, favorably-oriented grains: A. Chill B. Columnar C. Equiaxed D. Heat affected
Columnar
Useful shapes are generally created from crystalline ceramics by: A. Plastic deformation using rolling, forging and extrusion B. Melting and solidification C. Compaction of fine powders followed by sintering (pressing and firing)
Compaction of fine powders followed by sintering (pressing and firing)
Which of the following is NOT a correct statement regarding composite materials? A. Distinct interfaces are present between component materials B. The components can be metals, ceramics, polymers, or even natural materials C. Each component retains its identity, structure, and properties D. Composite materials can be easily separated and recycled
Composite materials can be easily separated and recycled
Tempered glass acquires its enhanced toughness or fracture resistance through: A. Compressive residual stresses B. A continuous metal matrix C. Weak interfaces between components D. A metastable phase that transforms
Compressive residual stresses
The dominant uses of copper and copper alloys utilize the properties of: A. Lightweight and corrosion resistance B. Strength and color C. Conductivity and corrosion resistance D. Elevated temperature strength and wear resistance
Conductivity and corrosion resistance
A martensitic steel is one that: A. Contains significant amounts of carbon and achieves much of its strength from phase transformation hardening B. Is the cheapest, and if it achieves most of its strength from solid solution strengthening C. Offers the greatest ductility and formability (because of its FCC crystal structure)
Contains significant amounts of carbon and achieves much of its strength from phase transformation hardening
Shrink voids can form during solidification because when a metal goes from liquid to solid, it generally: A. Contracts B. Expands
Contracts
In this type of bonding, the bonds are "directional" (wanting a set and limited number of nearest neighbors). The resulting materials have relatively low density. A. Metallic B. Ionic C. Covalent D. Vander Waals
Covalent
In linear polymers, the bonding along the length of the fiber or chain is ____, but the bonding attraction between the molecular fibers or chains is ____. A. Ionic, covalent B. Covalent, ionic C. Covalent, vanderWaals D. VanderWaals, covalent
Covalent, VanderWaals
A stress-rupture diagram, including lines for various temperatures, is a compilation of data from multiple ___ tests. A. Tensile B. Impact C. Fatigue D. Creep E. Hardness
Creep
The endurance limit is one measurement of a material's ability to endure: A. Cyclic loadings B. Impact loads C. Elevated temperatures D. Wear conditions
Cyclic loadings
When a precipitate grows to the point where it loses "coherency" and becomes a distinct second phase, the strength of the material: A. Increases B. Decreases C. Remains unchanged
Decreases
To be age hardenable, an alloy should display a phase diagram with: A. increasing solubility with decreasing temperature B. Decreasing solubility with decreasing temperature
Decreasing solubility with decreasing temperature
The type of crystalline defect whose movement provides the plastic deformation observed in ductile metals is the: A. Vacancy B. Substitutional C. Dislocation D. Grain Boundary
Dislocation
The strength increase observed during strain hardening is primarily due to an enormous increase in the number or amount of: A. Substitutional atoms B. Dislocations C. Interstitial atoms D. Vacancies
Dislocations
This type of cast iron, that offers properties closest to steels, contains smooth-surface graphite spheres that form directly upon solidification. A. Gray B. White C. Malleable D. Ductile E. Compacted graphite
Ductile
The "ductility" of a material can be measured by which two tensile test properties? A. Young's modulus and tensile strength B. Tensile strength and elongation C. Elongation and reduction in area D. Elongation and Young's modulus
Elongation and reduction in area
The activation energy (the Q in the D= De^(-Q/RT)) is a measure of the: A. Number of atoms passing across a plane in a given time B. Energy required to cause an atom to move position within a crystal C. Distance an atom will move in a single jump
Energy required to cause an atom to move position within a crystal
Because the properties of this internal region of a casting are attractive, inoculation may be used to promote its formation or increase its size: A. Chill B. Columnar C. Equiaxed D. Heat affected
Equiaxed
Which of the following reactions occurs entirely in the solid state? A. Eutectic B. Eutectoid C. Peritectic D. Monotectic
Eutectoid
Upon cooling, iron changes from FCC to a BCC. Because of the relative packing factor efficiencies of these structures, iron will __ when it transforms from FCC to BCC. A. Contract B. Expand C. Remain unchanged
Expand
Because this structure has four non-parallel slip planes {111} with three slip directions in each for a total of 12 slip systems, it exhibits exceptional ductility. A. BCC B. FCC C. HCP
FCC
Cold working is an effective means of strengthening materials with this crystal structure A. SC B. BCC C. FCC D. HCP
FCC
In the face-centered cubic (FCC) crystal structure, atoms touch along the: A. Cube edges B. Body diagonals C. Face diagonals
Face diagonals
To form smaller, more numerous grains and a stronger material, the cooling rate should be: A. Fast B. Slow
Fast
Ninety percent of all mechanical component failures occur as a result of : A. Tensile B. Impact C. Fatigue D. Creep
Fatigue
Parallel line striations and "beach marks" that appear on fracture surfaces are characteristic of failure by this means: A. Tensile B. Impact C. Fatigue D. Creep
Fatigue
Cast irons are alloys of: A. Fe-Si-Cr B. Fe-C-Si C. Fe-C-Cr D. Fe-Cr-Ni
Fe-C-Si
The room- temperature (BCC) form of iron that can only contain up to .02% carbon in solid solution is called: A. Ferrite B. O-Ferrite C. Austenite D. Cementite
Ferrite
The crystalline ceramics are brittle becasue: A. Their structures do not contain dislocations B. Fracture occurs at a lower stress than dislocation movement C. The structures involve highly cross-linked molecules
Fracture occurs at a lower stress than dislocation movement
Which of these process heat treatments produces the weakest, most ductile product for any carbon content steel? A. Process Anneal B. Full anneal C. Normalize D. Spheroidize
Full anneal
The third and final step of a three-step age hardening heat treatment would be to: A. Heat to a temp between the liquidus and solidus B. Heat to the single phase region and hold to produce a homogeneous solid C. Heat the super saturated phase material to a temperature below the solvus where the second phase will precipitate
Heat the super saturated phase material to a temperature below the solvus where the second phase will precipitate
The initial first step of a three- step age hardening heat treatment would be to: A. Heat to a temp between the liquidus and solidus B. Heat to the single phase region and hold to produce a homogeneous solid C. Heat the super saturated phase material to a temperature below the solvus where the second phase will precipitate
Heat to the single phase region and hold to produce a homogeneous solid
Which of the following is a significant limitation to the use of copper and copper alloys? A. Poor formability B. Poor conductivity C. Heavier than steel D. Poor corrosion resistance
Heavier than steel
Which type of nucleation is promoted by adding impurity particles to the melt (inoculation)? A. Homogeneous B. Heterogeneous
Heterogeneous
Which of the following is NOT a characteristic of gray cast iron? A. Good resistance to sticking (adhesive) wear B. Good sound and vibration damping C. High fracture resistance D. Good machinablity
High fracture resistance
Which type of nucleation is rarely observed during normal solidification? A. Homogeneous B. Heterogeneous
Homogeneous
The tests done at Missouri S&T (then UMR) to investigate the brittleness of the hull plate steel from the HMS Titanic were this type of test: A. Tensile B. Impact C. Fatigue D. Creep E. Hardness
Impact
As the temperature is increased in the range of atomic diffusion, we would expect the rate of atom movement to ___ with temperature. A. Increase linearly B. Decrease linearly C. Increase exponentially D. Decrease exponentially
Increase exponentially
If we increase "hardenability" we: A. Increase the Rockwell C hardness B. Increase the ease of forming martensite
Increase the ease of forming martensite
Plastically deforming of "Cold working" a thermoplastic polymer would: A. Increase the strength of the resulting polymer B. Decrease the strength of the resulting polymer C. The strength of the polymer does not depend on deformation
Increase the strength of the resulting polymer
Replacing hydrogen side atoms with chlorine to form a copolymer would: A. Increase the strength of the resulting polymer B. Decrease the strength of the resulting polymer C. The strength of the polymer does not depend on the side atoms
Increase the strength of the resulting polymer
Adding imperfections to a commercial metal (one that already contains defects) will almost always __ the strength and __ the ductility. A. Increase, increase B. Increase, decrease C. Decrease, increase D. Decrease, decrease
Increase, increase
As the carbon content of the steel increases, the strength and hardness of the resulting martensite: A. Increases B. Decreases
Increases
The bonding in ceramic materials is: A. Ionic and metallic B. Covalent and metallic C. Ionic and covalent D. Covalent and van derWaals
Ionic and covalent
A ferritic stainless steel is one that: A. Contains significant amounts of carbon and achieves much of its strength from phase transformation hardening B. Is the cheapest, and if it achieves most of its strength from solid solution strengthening C. Offers the greatest ductility and formability (because of its FCC crystal structure)
Is the cheapest, and if it achieves most of its strength from solid solution strengthening
Because of the type of bond, diffusion would be easiest to activate in materials with ___ bonding. A. Ionic B. Covalent C. Metallic
Metallic
If the size of nucleating solid is greater that the critical radius for a given temperature,____: A. It will remelt, ex return to liquid B. It will continue to grow into a larger solid C. It will divide and create additional nuclei
It will continue to grow into a larger solid
In Fick's First Law, J= -D(dc/dx), the resultant movement of atoms (flux) is represented by this term: A. J B. D C. dc D. dx
J
Dual-phase steels are quenched from a temp that is: A. Just above the A1 B. midway between the A3 and A1 C. Above the A3
Just above the A1
Because of their geometries, the properties of ____ composites are always anisotropic A. Laminar B. Particulate C. Fiber reinforced
Laminar
Plywood, safety glass, bimetallic strip and Alclad are all examples of this type of composite A. Laminar B. Particulate C. Fiber-reinforced
Laminar
The thermodynamic term for the amount of heat energy released when liquid cools to a solid is: A. Specific Heat B. Superheat C. Latent heat of fusion D. Undercooling
Latent heat of fusion
In a crystalline lattice, the distance between adjacent lattice points (in a specified direction) is the: A. Miller index B. Lattice parameter C. Packing factor D. Coordination Number
Lattice parameter
The aspect ratio of a reinforcing fiber is the ratio of its: A. Strength to stiffness B. Strength to density C. Length to diameter D. Density to that of the matrix
Length to diameter
If we were to add 5% nickel to pure copper to produce a copper-5% nickel alloy, the ductility of the alloy would be ___ the ductility of pure copper. A. Greater than B. The same as C. Less than
Less than
Compared to aluminum, magnesium alloys are: A. Stronger B. Lighter C. More ductile D. More corrosion resistant
Lighter
Carbon is an interstitial atom when dissolved in iron. Because it is an interstitial, the solubility of carbon would definitely be: A. Zero B. Limited C. Unlimited
Limited
The temperature below which a material begins to solidify upon cooling is called the: A. Freezing range B. Liquidus C. Solidus D. Solvus
Liquidus
This type of cast iron, which is extremely hard and used almost exclusively for its outstanding wear resistance, has all of its high carbon in the form of Fe3C. A. Gray B. White C. Malleable D. Ductile E. Compacted graphite
Malleable
The true equilibrium form of carbon in iron-carbon alloys is: A. Cementite B. Austenite C. Martensite D. Graphite
Martensite
Which of the following structures is NOT a mixture of ferrite and cementite? A. Pearlite B. Bainite C. Martensite D. Tempered martensite
Martensite
Met 2110 focuses on which step in the manufacturing sequence? A.Material Selection B. Process selection C. Manufacture or fabrication D. Evaluation
Material Selection
Residual stresses produced by cold working: A. Are always detrimental B. May be advantageous or detrimental C. Are always advantageous
May be advantageous or detrimental
Because the electrons in this type of bonding are not captive to either atoms or locations, but are free to wander throughout the structure, electrical and thermal conductivities are good, and the materials are often ductile. A. Metallic B. Ionic C. Covalent D. Vander Waals
Metallic
Materials in this family often exhibit good strength and good ductility. They are also good electrical and thermal conductors. A. Metals B. Ceramics C. Polymers
Metals
When we need useful strength and corrosion resistance at elevated temperature, we might want to consider alloys of: A. Aluminum B. Copper C. Nickel D. Magnesium
NIckel
The superalloy metals are based on which two metals? A. Nickel and cobalt B. TItanium and copper C. Tungsten and molybdenum D. Beryllium and magnesium
Nickel and cobalt
Since glass is a(n) ___ structure, its formation requires cooling at a rate that is ____ than some critical value. A. Equilibrium, slower B. Equilibrium, faster C. Nonequilibrium, slower D. Nonequilibrium, faster
Nonequilibrium, faster
Which of these process heat treatments cools steel in air during the transformation process? A. Process anneal B. Full Anneal C. Normalize D. Spherodize
Normalize
Copper and zinc are similar-size atoms. If zinc atoms are added to copper, they would be expected to: A. Occupy interstitial sites B. Occupy substitutional sites. C. Become vacancies
Occupy Substitutional sites
Carbon atoms are much smaller than iron atoms. We would expect the carbon atoms to: A. Occupy interstitial sites B. Occupy substitutional sites. C. Lie on grain boundaries
Occupy interstitial sites
An austenitic stainless steel is one that: A. Contains significant amounts of carbon and achieves much of its strength from phase transformation hardening B. Is the cheapest, and if it achieves most of its strength from solid solution strengthening C. Offers the greatest ductility and formability (because of its FCC crystal structure)
Offers the greatest ductility and formability (because of its FCC crystal structure)
Since it would be the least tightly bonded, the lowest temperature would be required to activate movement of an atom lying: A. On a free surface B. Along a grain boundary C. Within a crystal
On a free surface
In order to move a dislocation, we must A. Break all the bonds over an entire surface or plane of atoms B. Only break the bonds along a row or line of atoms C. Only break the bonds to a single or individual atom
Only break the bonds along a row or line of atoms
If an age-hardened aluminum-copper alloy is reheated to diffusion temperatures, the result will likely be: A. Overaging and an increase in strength B. Overaging and a loss of strength C. A decrease in ductility
Overaging and a loss of strength
Because of their geometries, the properties of ____ composites are always isotropic. A. Laminar B. Particulate C. Fiber reinforced
Particulate
The lamellar or layered structure, consisting of alternating plates of ferrite and cementite, is called: A. Cementite B. Pearlite C. Austenite D. Ferrite
Pearlite
The microstructure that forms above the "nose" in a eutectoid steel T-T-T diagram is: A. Pearlite B. Bainite C. Martensite
Pearlite
Ceramic materials excel when: A. Mechanical properties dominate the selection process B. Physical properties dominate the selection process
Physical properties dominate the selection process
If the liquid ahead of a growing solid has a temp higher than the melting point, growth into the liquid will be: A. Dendritic growth B. Planar growth
Planar growth
Which of the following is NOT a limitation of aluminum? A. Poor thermal conductivity B. Poor wear resistance C. Low stiffness D. Poor in fatigue
Poor thermal conductivity
Which of the following techniques is used to impart enhanced rigidity and dimensional stability to the rubbery elastomers? A. Produce longer chains B. Promote cross-linking C. Initiate branching D. Cold work (deform) the polymer
Promote cross- linking
In a fiber-reinforced composite, we ask the matrix material to do all of the following EXCEPT: A. Provide strength and stiffness B. Provide ductility and toughness C. Support the fibers D. Provide desired electrical or thermal conductivity
Provide strength and stiffness
Which of the following is NOT a standard condition for the tensile test? A. Rapid rate of loading B. Diameter of .505 inches C. Room Temp D. Gage length of 2 inches
Rapid rate of loading
The stage of annealing where the residual stresses from cold working are eliminated, but the strengthening remains is: A. Recovery B. Recrystallization C. Grain Growth
Recovery
The stage of annealing where the effects of strain hardening are removed, and ductility is restored is: A. Recovery B. Recrystallization C. Grain Growth
Recrystallization
The stage of annealing where the number of dislocations decreases significantly is: A. Recovery B. Recrystallization C. Grain Growth
Recrystallization
The use of advanced ceramics is most limited by the inability to: A. Control material purity B. Control sintering time and temperature C. Reduce flaw size
Reduce flaw size
Metallic-bonded materials prefer crystal structures with dense packing and a large number of nearest neighbors. The LEAST attractive structure is ___ since it has only ___ neighbors. A. SC -- 6 B. BCC -- 8 C. SC -- 8 D. BCC -- 6
SC -- 6
The Hume-Rothery rules for unlimited solid solubility between two metals include all of these similarities EXCEPT: A. Same crystal structure B. Similar electronegativity or valence C. Similar strength D. Similar atomic radii
Similar strength
A material with a ASTM grain size of 8 would have __ crystals compared to one of ASTM 4. A. Smaller B. The same size C. Larger
Smaller
Increasing the cooling rate of a eutectic material will produce a structure with ___ interlamellar spacing (or layer thickness) and ___ strength. A. Smaller, higher B. Smaller, lower C. Larger, lower D. Larger, higher
Smaller, higher
Ideally, we would like the matrix of an age hardenable alloy to be: A. Hard and brittle B. Soft and ductile
Soft and ductile
The temperature at which a material is fully solidified is called the: A. Freezing range B. Liquidus C. Solidus D. Solvus
Solidus
Which of the following is NOT an attractive feature of adhesive bonding? A. The joints offer good strength at elevated temperatures (in excess of 500F) B. All materials and combinations can be joined C. The adhesive can provide noise and vibration damping D. Adhesives are light in weight
The joints offer good strength at elevated temperatures (in excess of 500F)
In the plastic region of the tensile test: A. The material is always getting stronger B. The material gets stronger only up to the tensile strength C. The material gets weaker due to dislocation movement
The material is always getting stronger
During hot working, the material is deformed at which temperatures? A. The melting temp. B. Room temp. C. The recrystallization temp.
The recrystallization temp
Plastic deformation commences when: A. The resolved shear stress equals the critical resolved shear stress B. The applied stress equals the critical resolved shear stress
The resolved shear stress equals the critical resolved shear stress
If one steel alloy has a flat hardenability curve and a maximum hardness of Rockwell C 35 and another steel alloy has a hardenability curve that drops off quickly as Jd Increases, but a maximum hardness of Rockwell C 65, which steel alloy has the highest carbon content? A. The steel with the flat hardenability curve B. The steel with the steep hardenability curve C. The steel with hardness of Rockwell C 35 D. The steel with hardness of Rockwell C 65
The steel with the hardness of Rockwell C 65
The Rule of Mixtures predicts properties based on: A. The size, shape and distribution of the components B. The volume fractions of the component materials C. The orientation of the component materials
The volume fractions of the component materials
The most easily recyclable polymers are almost always: A. Thermoplastics B. Thermosets C. Elastomers
Thermoplastics
Polymers of this type tend to have the highest strength and highest rigidity. Two-part epoxy is an example: A. Thermoplastic B. Thermoset C. Elastomer
Thermoset
This is the only lightweight metal that is also considered to be an "elevated temperature" material, retaining useful strength up through 500C or 900F A. Aluminum B. Beryllium C. Magnesium D. Titanium
Titanium
This metal can offer strength comparable to heat-treated medium-carbon steel at a little more than half the weight of steel, and is often found in aerospace applications. A. Aluminum B. Beryllium C. Magnesium D. Titanium
Titanium
Engineering strain is defined as: A. applied load/ original area B. Applied load/ actual area C. Total stretch/ original length D. The slope in the elastic region
Total stretch/ original length
Which of the following is considered a refractory metal? A. Tungsten B. Magnesium C. Aluminum D. Nickel
Tungsten
Which of the following is considered a refractory metal? A. Tungsten B. Magnesium C. Aluminum D. Nickel
Tungsten
Linear or chain-type polymers form when the reacting mers have a functionality of: A. One B. Two C. Three or more D. Any of these
Two
Dispersion-strengthened particulate composites are generally formed to extend or enhance the: A. Useful temperature range of a material B. Material toughness C. Material's ductility D. Material rigidity
Useful temperature range of a material
The two most common mechanisms for atom movement (diffusion) are: A. Vacancy and ring B. Vacancy and interstitial C. Ring and interstitial D. Dislocation and grain boundary
Vacancy and interstitial
All of the bonding electrons are tied up within molecules in this type of bonding. If the charge is not distributed uniformly within the molecules, a weak electrostatic attraction can occur between the polarized molecules. Its effects are often significant in polymeric materials. A. Metallic B. Ionic C. Covalent D. Vander Waals
Vander Waals
When fabricating products from thermoplastic polymers, production may be slowed because we must: A. Wait for the polymer to cool in the mold before it can be ejected. B. Provide time for the resin to cure in the mold before ejection C. Alloy time for the material to sufficiently cross-link
Wait for the polymer to cool in the mold before it can be ejected
This type of cast iron, which is extremely hard and used almost exclusively for its outstanding wear resistance, has all of its high carbon in the form of Fe3C. A. Gray B. White C. Malleable D. Ductile E. Compacted graphite
White
An aluminum alloy has the designation 3003-H14. This alloy would be a: A. Wrought alloy B. Casting alloy
Wrought alloy
What is the difference between wrought and cast alloys? A. Wrought is single-phase, cast is multi-phase B. Wrought is heat-treated, cast are not-heat-treated C. Wrought is shaped as a solid, cast is shaped as a liquid D. Wrought is strengthened by age hardening, cast is cold worked
Wrought is shaped as a solid, cast is shaped as a liquid
The first signs of permanent or plastic deformation are most closely associated with this value on a tensile test curve: A. Yield point B. Tensile strength C. Breaking strength
Yield point
To be age hardenable, an alloy should be precipitates that are: A. Hard, brittle and incoherent B. Hard, brittle and coherent C. Soft, ductile and incoherent D. Soft, ductile and coherent
hard, brittle and coherent