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MSE Exam 3 V11

Terms in this set (127)

In the growth of a phase (or crystallization) equation, the value of n is typically
A. Between 0.5 and 5
B. Below 0.5
Above 5
A
Martensite is the strongest of the common phases formed in steel. True or false
True
...
...
Based on the following phase diagram, what is the degree of freedom at point E at constant pressure?

A. 0
B. 1
C. 2
D. 3
A. 0
Don't add this,
NEEDED TO CREATE SET
Which of the following statement is correct
A) Nucleating agent should have good wetting behavior in molten material for it to be an effective nucleating agent
B) nucleating agent should not have good wetting behavior in a molten material for it to be an effective nucleating agent
C) wetting behavior has no role in determining if the nucleating agent will be effective
A
at eutectoid point (727 C, .77 wt % C), austentite steel (y-Fe) is in equilibrium with which of the following?
A) a-Fe
B) Fe3C
C) a-Fe and Fe3C
C
which one of the following is NOT a single-component system composed of two phases
A) a mixture of pure ice and pure water
B) a mixture of BCC and FCC iron
C) a mixture of Fe and C
D) none of the above
C
which one of the following is the strongest structure in steel
A) Pearlite
B) Bainite
C) Martensite
D) All of the above have comparable strength
C
Based on the following phase diagram, what is the composition of liquid for alloy 4?
A. 40% component A + 60% component B
B. 80% component A + 20% component B
C. 20% component A + 80% component B
D. None of the above
B
Based on the following phase diagram, for alloy 1 (X =0.125 wt. C), what is the weight percent of liquid just above peritectic isotherm?
A. 0.08
B. 0.920
C. 0
D. None of the above
A
Spheroidized microstructure is the most stable microstructure in steel
True
False
True
Which one of the following represents eutectic reaction?
A. Liquid ⇋ solid 1 + solid 2
B. Liquid + solid 1 ⇋ solid 2
C. Neither of the above
A
Based on the following phase diagram, which statement is true?
A. The fraction of liquid for alloy 4 is (0.6-0.2)/(0.8-0.2)
B. The composition of liquid of alloys 1, 2, 3, and 4 is the same
C. The composition of solid of alloys 2, 3, 4, and 5 is different
D. None of the above
B
Nucleation rate as a function of temperature can be given by which one of the following curves?
Based on the following figure, which of the following statement is true?
A. Diffusional transformation occurs below the temperature Ms
B. A thermal transformation is responsible for the forma of Pearlite and Bainite phases
C. Line M90 represents a temperature where 90 % of the material has been converted to martensite steel
C.
Which one of the following statement is correct?
A. Coherent interface leads to homogeneous nucleation
B. Coherent interface leads to heterogeneous nucleation
C. Incoherent interface leads to homogeneous nucleation
D. None of the above
A
Is it possible to suppress the formation of proeutectoid ferrite by rapid quenching and isothermal holds?
Yes
Which one of the following represents eutectic reaction?
A. Liquid <-> solid 1 + solid 2
B. Liquid + solid 1 <-> solid 2
C. None of the above
A.
This eutectoid steel is equilibrated at 750°C, then quenched instantaneously to 350°C, held at that temperature for 1000 seconds. For this processing condition, which structure will be formed?
A. 100 % Martensite
B. About 50% Pearlite + 50% Bainite
C. About 50% (Pearlite + Bainite) + 50% Martensite
D. None of the above
C
Interfacial energy of a spherical solid particle in a liquid is proportional to ________?
A. (4πr^3)/3
B. 4πr^2
C. 2 πr
D. None of the above
B
Gibbs phase rule at constant pressure is given by which of the following equation? (Symbols have their usual meaning)
(A) F = C - P + 2
(B) F = C - P + 3
(C) F = C - P + 1
(D) none of the above
(C) F = C - P + 1
Which one of the following represents eutectic reaction?
A. Liquid ⇌ solid 1 + solid 2
B. Liquid + solid 1 ⇌ solid 2
C. Neither of the above
A. Liquid ⇌ solid 1 + solid 2
...
...
Gibbs phase rule at constant pressure is given by which of the following equatioins?

A. F=C-P+2
B. F=C-P+3
C. F=C-P+1
D. None of the above
C
Based on the phase diagram, what is the degree of freedom at point E at constant pressure?

A. 0
B. 1
C. 2
D. 3
A
Martensite steel has the following crystal structure

A. FCC
B. Simple Cubic
C. BCC
D. None of the above
D
Which statement is correct?

A. Coherent interface leads to homogenous nucleation
B. Coherent interface leads to heterogenous nucleation
C. Incoherent interface leads to homogenous nucleatioin
D. None of the above
A
Spheroidized microstructure is the most stable microstructure in steel.

True
False
True
Estimate the maximum amount of proeutectoid ferrite that can form in a plain carbon steel containing .75 wt% carbon

A. .9733
B. .0266
C. .5832
D. .4168
B
When austenite steel with .77 wt% carbon is cooled to below 200 C, then which of the following statement is correct?

A. It forms a 2 phase mixture of a-Fe and Fe3C referred to as pearlite or bainite
B. It results in martensite steel
C. Both
B
White one of the following represents eutectic reaction?

A. liquid = soliid 1 + solid 2
B. liquid + solid 1 = solid 2
C. Neither
A
The phase boundary separating a solid region from a two-phase solid region is referred as ______.
A. Isotherm
B. Liquidus
C. Solidus
D. Solvus
Solvus
When austenite steel, with a composition of .77 wt% carbon, is cooled to 650, 600, and 550c, then the thickness of Fe3C layers will be in the following order?
A. 550 >600>650
B. 600>550>650
C. 650>600>550
D. None of the above
C
Which of the followings are examples of nucleating agent(s) that promote heterogeneous nucleation?
A. TiO2
B. TiB2
C. Mold wall
D. All of the above
E None of the above
D
Hypoeutectoid steel contains _____.
A. <0.77 wt% C
B. = 0.77 wt% C
C. > .77 wt% C
D. 6.7 wt% C
A
When austenite steel is cooled to 650 C and then held for 100 seconds, the structure will be _____.
A. Pearlite
B. Bainite
C. Martensite
D. None of the above
A
Which of the following can produce martensite from a rapid quench?
A. Austenite
B. Pearlite
C. Bainite
D. None of the above
A
What type of interface tends to have lowest interfacial energy?
A. Coherent interfaces
B. Semi-coherent interfaces
C. Incoherent interfaces
D. None of the above
A
Pearlite layers are thicker at 650 °C ( after holding for 100 seconds)than at 600 °C (after holding for 100 seconds). Is this statement true or false?
True
False
True
This eutectoid steel is equilibrated at 750°C, then quenched instantaneously to 350°C, held at that temperature for 1000 seconds. For this processing condition, which structure will be formed?
A. 100 % Bainite
B. 100 % Pearlite
C. 50% Pearlite + 50% Bainite
D. None of the above
A
A mixture of BCC iron and FCC iron is an example of _________.
(A) two component system
(B) two phase system
(C) both (A) and (B) are correct
B
Based on the following phase diagram, what is the composition of liquid at T3?
(A) 0.57 A
(B) 0.68 A
(C) 0.60 A
(D) 0.65 A
(E) none the above
E
In the following phase diagram, what's the fraction of liquid for alloy 4?
(A) 0.5
(B) 2/3
(C) 1/3
(D) None of the above
C
Sn and Pb melt at 232 and 327 °C, respectively. However, an alloy containing 69.1 % Sn and 38.1 % Pb melt at 183 °C, which is lower than the melting point of either metal. Based on this information, Sn and Pb alloy is an example of _______.
(A) normal solution
(B) congruent melting
(C) both A and B
(D) none of the above
B
In the eutectic phase diagram, where can three phases co-exist?
(A) At the liquidus boundary
(B) At the solidus boundary
(C) At the solvus boundary
(D) At the eutectic point
D
Based on the following phase diagram, for alloy 2 (X2=0.17 wt. % C), what is the weight percent of δ-Fe just above peritectic isotherm?
(A) 0.182
(B) 0.818
(C) 0
(D) none of the above
B
The typical energy for incoherent interface is ______.
A. 200 mJ/m2
B. 500 mJ/m2
C. 1000 mJ/m2
D. 10,000 mJ/m2
C
In general, for the interfacial energy, which one of the following is correct?
A. Energy of incoherent interface > energy of coherent interface
B. Energy of coherent interface > energy of incoherent interface
C. Energy of semi-coherent interface < energy of coherent interface
D. Energy of semi-coherent interface > energy of incoherent interface
A
Based on the following figure, which of the following statement is true?
A. Diffusional transformation occurs below the temperature Ms
B. A thermal transformation is responsible for the formation of Pearlite and Bainite phases
C. Line M90 represents a temperature where 90 % of the material has been converted to martensite steel
C
Which of the following is the example of types of interface between two solid interfaces:
A. Coherent interface
B. Semi-coherent interface
C. Incoherent interface
D. All of the above
E. Only coherent and incoherent interface
D
Estimate the maximum amount of austenite that can form in a plain carbon steel containing 0.75 wt% carbon.
A. 0.9733
B. 0.0266
C. 0.5832
D. 0.4168
A
Nucleating agents can be used in which of the following to seed crystallization?
A. Polymer
B. Ceramics
C. Metals
D. All of the above
E. None of the above
D
For an alloy containing 88% B, what is the percentage or fraction of the solid at T4.
A. (88 - 75)/(95 - 75)
B. (95 - 88)/(95 - 75)
C. 95 % B
D. 75 % B
E. None of the above
A
Pearlite layers are thicker at 650 °C (after holding for 100 seconds) than at 600 °C (after holding for 100 seconds). Is this statement true or false?
True
False
True
Based on the phase diagram above, what is the degree of freedom in region I at constant pressure?
A. 0
B. 1
C. 2
D. 3
B
Growth of a phase or crystallization is given by which one of the following equations.
A. X = 1- exp[-(kt)^n]
B. X = 1+ exp[-(kt)^n]
C. X = 1- exp[+(kt)^n]
D. None of the above
A
Interfacial energy of a spherical solid particle in a liquid is proportional to ________?
A. (4πr^3)/3
B. 4πr^3
C. 2 πr
D. None of the above
D
100% Bainite steel can be converted to martensite steel by simply cooling it to below 200 °C. This statement is __________.
True
False
False
Martensite steel has the following crystal structure?
A. BCT (Body-centered tetragonal)
B. Simple cubic
C. BCC (Body-centered cubic)
D. FCC (Face-centered cubic)
A
Based on the following phase diagram, which statement is true?
A. The fraction of liquid for alloy 4 is (0.6 - 0.2)/(0.8 - 0.2).
B. The composition of liquid of alloys 1, 2, 3, and 4 is same.
C. The composition of solid of alloys 2, 3, 4, and 5 is different.
D. None of the above.
B
Which one of the following is NOT a single-component system composed of two phases?
A. A mixture of pure ice and pure water
B. A mixture of BCC iron and FCC iron
C. A mixture of Fe and C
D. None of the above
C
Sn and Pb melt at 232 and 327 °C, respectively. However, an alloy containing 69.1 % Sn and 38.1 % Pb melt at 183 °C, which is lower than the melting point of either metal. Based on this information, Sn and Pb alloy is an example of incongruent melting. This statement is _____.
True
False
False
The gibbs free energy barrier (ΔG) for nucleation is inversely proportional to (ΔT)^2. This statement is __________.
True
False
True
Compositions to the left part (X < XE) of the following phase diagram are referred to as ___________________.
A. Hypereutectic
B. Hypoeutectic
C. Peritectic
D. None of the above
B
Based on the following phase diagram, for alloy 2 (X2=0.17 wt. % C), what is the weight percent of γ-Fe just below peritectic isotherm?
(A) 0
(B) 0.818
(C) 1
(D) none of the above
(C) 1
In the following phase diagram, which region has 1 degree of freedom at constant pressure?
(A) The liquid region.
(B) The solid region.
(C) The liquid+solid two-phase region.
(D) Both liquid and solid regions.
(C) The liquid+solid two-phase region.
Compositions to the right part (X > XE) of following phase diagram are referred to as ___________________.
(A) hypereutectic
(B) hypoeutectic
(C) peritectic
(D) none of the above
(A) hypereutectic
Based on the following phase diagram, for alloy 3 (X3=0.35 wt. % C), what is the weight percent of γ-Fe just above peritectic isotherm?
(A) 0.591
(B) 0.409
(C) 0
(D) none of the above
(C) 0
Based on the following phase diagram, for alloy 2 (X2=0.17 wt. % C), what is the weight percent of δ-Fe just above peritectic isotherm?
(A) 0.182
(B) 0.818
(C) 0
(D) none of the above
(B) 0.818
Which of the following statement is INCORRECT?
A. At the melting temperature, there is zero change in Gibbs free energy in going from solid to liquid or vice versa.
B. At the melting temperature, the liquid phase and solid phase are in equilibrium.
C. △S L→S = △H L→S/Tm
D. △H L→S is positive
E. △S L→S is negative
D. △H L→S is positive
Which of the following is correct?
A. Homogeneous nucleation occurs at random location
B. Heterogeneous nucleation occurs at random locations
C. Homogeneous nucleation occurs at impurity sites
D. Homogeneous nucleation occurs at walls of the mold.
A. Homogeneous nucleation occurs at random location
Martensite phase is very stable and will not change upon heating to 600 °C. Is this statement true or false?
True
False
False
What does the following microstructure represent?
A. Alpha Ferrite
B. Gamma
C. Pearlite
D. Martensite
C. Pearlite
Martensite steel has the following crystal structure?
A. FCC
B. Simple cubic
C. BCC
D. None of the above
D. None of the above
Nucleation can occur at __________.
A. Random locations in a given liquid
B. At impurities present in a given liquid
C. At the walls of the liquid container
D. All of the above
E. None of the above
D. All of the above
Which of the following statement is correct?
A. Nucleating agent should have good wetting behavior in a molten material for it to be an effective nucleating agent
B. Nucleating agent should not have good wetting behavior in a molten material for it to be an effective nucleating agent
C. Wetting behavior has no role in determining if the nucleating agent will be effective
A. Nucleating agent should have good wetting behavior in a molten material for it to be an effective nucleating agent
Based on the following phase diagram, which statement is true?
A. The fraction of liquid for alloy 4 is (0.6 - 0.2)/(0.8 - 0.2).
B. The composition of liquid of alloys 1, 2, 3, and 4 is same.
C. The composition of solid of alloys 2, 3, 4, and 5 is different.
D. None of the above.
B. The composition of liquid of alloys 1, 2, 3, and 4 is same.
Nucleating agents can be used in polymer, ceramic and metals to seed crystallization. Is this statement true or false?
True
False
True
Formation of martensite structure is dependent on temperature but independent on time. Is this statement true or false?
True
False
True
For alloy 1 (X1=0.125 wt. % C), what is the weight fraction of δ-Fe just above peritectic isotherm?
A. (0.125 - 0.09)/(0.53 - 0.09)
B. (0.53 - 0.125)/(0.53 - 0.09)
C. (0.17 - 0.125)/(0.17 - 0.09)
D. None of the above
B. (0.53 - 0.125)/(0.53 - 0.09)
What is the maximum solid solubility of B in a?

A. 10 %
B. 37 %
C. 65 %
D. 90 %
B. 37 %
Based on the following phase diagram, what is the mass fraction of solid at T3 for alloy 1?
A. (0.60 - 0.55)/(0.65 - 0.55)
B. (0.65 - 0.60)/(0.65 - 0.55)
C. (0.70 - 0.60)/(0.70 - 0.48)
D. none of the above
A. (0.60 - 0.55)/(0.65 - 0.55)
Hypereutectoid steel contains ________.
A. < 0.77 wt % C
B. = 0.77 wt % C
C. > 0.77 wt % C
D. 6.7 wt % C
C. > 0.77 wt % C
Critical radius of nucleation decreases as the degree of undercooling (ΔT) increase. Is this statement true or false?
True
False
True
For alloy 3 (X3=0.35 wt. % C), what is the weight fraction of liquid just above peritectic isotherm?
A. (0.35 - 0.09)/(0.53 - 0.09)
B. (0.53 - 0.35)/(0.53 - 0.09)
C. (0.35 - 0.17)/(0.53 - 0.17)
D. None of the above
A. (0.35 - 0.09)/(0.53 - 0.09)
When eutectoid steel with Bainite structure is heated to above 1000 °C, and then quenched to -100 °C, it will result primarily in the following:
A. Martensite steel
B. Austenite steel
C. Pearlite steel
D. Bainite steel
E. None of the above
A. Martensite steel
Which of the following is an example of the two component system?
(A) H2O
(B) H2O +NaCl
(C) Fe + C
(D) all of the above
(E) only (B) and (C)
E
Based on the following phase diagram, what is the mass fraction liqued at T3 for alloy 1?
(A) (0.60 - 0.55)/(0.65 - 0.55)
(B) (0.65 - 0.60)/(0.65 - 0.55)
(C) (0.70 - 0.60)/(0.70 - 0.48)
(D) none of the above
B
Based on the following phase diagram, determine the composition of
the first solid to form when cooling the alloy at X1 from the liquid state?
(A) XS1 of B
(B) X1
(C) XL1
(D) None of the above
A
In the following phase diagram for water, the point having zero degree
of freedom is the ________________.
(A) boiling point
(B) melting point
(C) sublimation point
(D) triple point
D
Based on the following phase diagram, determine the composition of the last liquid to solidify when cooling the alloy at X2?
(A) XS2
(B) X2
(C)XL2 of B
(D) None of the above
C
Based on the following phase diagram, for alloy 1 (X =0.125 wt. % C),
what is the weight percent of δ-Fe just below peritectic isotherm?
(A) 0
(B) 0.563
(C) 0.437
(D) none of the above
B
Based on the following phase diagram, for alloys containing 50 wt. % Ni
at 1300°C, determine the number of phases present.
(A) 0
(B) 1
(C) 2
(D) 3
(E) none of the above
C
In the following phase diagram, which phases are in equilibrium at point A?
(A) α-iron and γ-iron
(B) γ-iron and ε-iron
(C) α-iron, γ-iron, and ε-iron
(D) none of the above is correct
C
Based on the following phase diagram, which one of the following
statement is true when solidifying 80 wt. % Ni alloy?
(A) the cooling rate has no effect on the microstructure of the alloy
when cooling from 1500 °C to room temperature
(B) only liquid phase exists at 1400 °C
(C) two phases exist at 300 °C
(D) none of the above
C
Based on the following phase diagrams (figures a, b, c and d), which one
of the following statements is true?
A) the clustering tendency of the solid decreases from figures (a) to (d)
(B) the clustering tendency of the solid is higher in figure (b) than in
figure (d)
(C) the clustering tendency of the solid increases from figure (a) to figure
(d)
(D) none of the above
C
The crystal structure of iron can be _______?
A. FCC only
B. BCC only
C. It can be either FCC or BCC
D. None of the above
C
What does the following microstructure represent?
A. Alpha Ferrite
B. Gamma
C. Pearlite
D. Martensite
D
Interfacial energy of a spherical solid particle in a liquid is proportional to ____?
A.(4πr^3)/3
B. 4πr^2
C. 2 πr
D. None of the above
B
When austenite steel with 0.77 wt % carbon is cooled to below 200 °C,
then which of the following statement is correct?
A. It forms a two phase mixture of α-Fe and Fe3C referred to as pearlite
or bainite.
B. It results in martensite steel.
B
Which of the following is the example of types of interface between
two solid interfaces:
A. Coherent interface
B. Semi-coherent interface
C. Incoherent interface
D. All of the above
E. Only coherent and incoherent interface
D
Based on the following figure, which of the following statement is true?
A. Diffusional transformation occurs below the temperature Ms
B. A thermal transformation is responsible for the forma of Pearlite and Bainite phases
C. Line M represents a temperature where 90 % of the material has been converted to martensite steel
C
Pearlite layers are thicker at 600 °C ( after holding for 100 seconds)
than at 650 °C (after holding for 100 seconds). Is this statement true or false?
False
Based on the JMA equatoin which one of the following equations can
determine the constant n in JMA equation at Temperature T if the
fraction of phase transformed at different times is given?
A. InIn(1/(1-x) )= nInt + nInK
B. InIn(1/(1-x) )= nInt - nInK
C. InIn( 1/(1-x))= - nInt - nInK
D. None of the above
A
Spheroidite microstructure of steel is formed by _______.
A. Heating the martensite phase to 600 C
B. By cooling the austentite phase to 600 C
A
For the addition of C in Fe, which of the following statement is
INCORRECT?
A. C exists in the interstices of Fe crystal
B. C can form iron carbide compound
C. Neither of the above is incorrect
C
For heterogeneous nucleation at a mold surface with a contact angle of
180°, which of the following relation is correct about the free energy barrier for nucleation?
A. dGhetero = dGhomo
B. dGhetero < dGhomo
C. dGhetero > dGhomo
D. dGhetero = 0
A
For alloy 3 (X =0.35 wt. % C), what is the weight fraction of γ-Fe just below peritectic isotherm?
A. (0.53 - 0.35)/(0.53 - 0.17)
B. (0.35 - 0.17)/(0.53 - 0.17)
C. 0
D. 1
E. None of the above
A
Which contact angle corresponds to complete wetting?
A. 0 degrees
B. 90 degrees
C. 180 degrees
D. None of above.
A
Which of the following statement is CORRECT?
A. At the melting temperature, there is zero change in Gibbs free energy in going from solid to liquid or vice versea
B. At the melting temperature, the liquid phase and solid phase are NOT in eqeuilibrium
C. Change in entropy (entropy of solid - entropy of liquid) at the melting temperature is positive
D. None of the above
A
Nucleating agent should have good wetting behavior in a molten material for it to be an effective nucleating agent.
True
False
True
For an alloy containing 88% B, what is the composition of the solid at T4?
A. 10 % B
B. 88 % B
C. 95 % B
D. 75% B
E. None of the above
C
Martensite steel has the following crystal structure?
A. BCT (Body-centered tetragonal)
B. Simple cubic
C. BCC (Body-centered cubic)
D. FCC (Face-centered cubic)
A
For an alloy containing 88% B, what is the percentage or fraction of the solid at T4?
A. (88 - 75)/(95 - 75)
B. (95 - 88)/(95 - 75)
C. 95 % B
D. 75 % B
E. None of the above
A
Which one of the following is the strongest structure in steel?
A. Pearlite
B. Bainite
C. Martensite
D. All the above are comparable
C
Diffusion is responsible for the formation of Pearlite and Bainite phases.
This statement is true or False.
True
False
True
Based on the phase diagram above, what is the degree of freedom in
region I at constant pressure?
A. 0
B. 1
C. 2
D. 3
B
Which one of the following is NOT a single-component system
composed of two phases?
A. A mixture of pure ice and pure water
B. A mixture of BCC iron and FCC iron
C. A mixture of Fe and C
D. None of the above
C
In the following figure about the energy barrier in homogeneous
nucleation, at what radius will the nucleus be spontaneously dissolved and not grow into a larger particle?
A. r < r*
B. r = r*
C. r > r*
D. None of the above
A
Growth of a phase or crystallization is given by which one of the following equations?
A. X = exp[-(kt)^n]
B. X = 1+ exp[-(kt)^n]
C. X = 1- exp[+(kt)^n]
D. None of the above
D
For alloy 1 (X =0.125 wt. % C), what is the weight fraction of δ-Fe just
above peritectic isotherm?
A. (0.125 - 0.09)/(0.53 - 0.09)
B. (0.53 - 0.125)/(0.53 - 0.09)
C. (0.17 - 0.125)/(0.17 - 0.09)
D. None of the above
B
Martensite steel has the same crystal structure as ferrite steel. Is this
statement true or false.
True
False
False
At constant temperature, Gibbs phase rule with varying pressure is given by which of the following equation?

A. F = C - P + 2
B. F = C - P + 3
C. F = C - P + 1
D. none of the above
C
This eutectoid steel is equilibrated at 750°C, then quenched
instantaneously to 480°C, held at that temperature for 3 seconds, and
finally quenched instantaneously to room temperature. For this processing condition, which structure will be formed?
A. Almost 100 % Martensite
B. About 50% Pearlite + 50% Bainite
C. About 50% (Pearlite +Bainite) + 50% Martensite
D. None of the above
C
100% Bainite steel can be converted to martensite steel by simply
cooling it to below 200 °C. This statement is __________.
True
False
False
This eutectoid steel is equilibrated at 750°C, then quenched
instantaneously to 350°C, and held at that temperature for 1,000
seconds. For this processing condition, which structure will be formed?
A. 100 % Bainite
B. 100% Pearlite
C. 50% Pearlite + 50% Bainite
D. None of the above
A
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