尔雅材料科学与工程基础（英文）答案(学习通2023题目答案)
54 min read尔雅材料科学与工程基础（英文）答案(学习通2023题目答案)
Chapter 1 Questions and Problems
1、尔雅One point one question
Chapter 2 Bonding
Test 1
1、材料Atomic weight (A) of an element corresponds to the weighted average of the atomic masses of the atom’s naturally occurring ___________.
A、科学ions
B、工程charges
C、基础isotopes
D、英文particles
2、答案Which of the following is 学习NOT an example of primary bonding?
A、Van der Waals
B、通题ionic
C、目答covalent
D、尔雅metallic
3、材料Covalent bonding occurs as a result of _________ sharing.
A、科学proton
B、工程electron
C、基础neutron
D、none of them
4、Bonds in most metals are referred to as ______.
A、Directional
B、Ionic
C、Non-directional
D、Covalent
5、If the electron configuration of Fe is 1s2 2s2 2p6 3s2 3p6 3d6 4s2, then the electron configurations for the Fe3+ is 1s2 2s2 2p6 3s2 _____.
A、3p6 3d5
B、3p8 3d3
C、3d6 3p5
D、3d6 4s2 4p3
Chapter 2 Questions and Problems
1、One point one question
Chapter 3 Crystal Structure
Chapter 3 Questions and Problems
1、Chapter 3 Questions and Problems
Chapter 4 Imperfection
Chapter 4 Questions and Problems
1、one question one point
Chapter 5 Diffusion
Test 2
1、How many atoms does the face centered cubic unit cell contain?
A、Two
B、Four
C、Three
D、One
2、The crystal structure of Cu is ?
A、Simple cubic
B、FCC
C、BCC
D、HCP
3、The coordination number of BCC crystal structure is .
A、2
B、4
C、6
D、8
4、The atomic packing factor for FCC is .
A、0.74
B、0.68
C、0.8
D、1
5、Interstitial solid solution belongs to .
A、infinite solid solution;
B、finite solid solution;
C、unhomogeneous solid solution ;
D、substitutional solid solution
6、Substitutional atom (impurity) is an example of ______.
A、point defect
B、linear defect
C、planar defect
D、bulk defect
7、One explanation for why graphite powder acts so well as a “solid lubricant”is .
A、carbon atoms in graphite are covalently bonded within planar layers but have weaker secondary bonds between layers
B、finely-powdered carbon has many unsatisfied bonds at the particle surfaces, which act as a “sea of electrons”to cause lubrication
C、when crushed into a fine powder, graphite establishes a “polar” distribution of charge, leading to Coulombic repulsion between powder particles
D、None of above
8、A ____ may form when impurity atoms are added to a solid, in which case the original crystal structure is retained and no new phases are formed.
A、defect
B、solid solution
C、chemical compound
D、metal
9、Edge and screw dislocations differ in what way?
A、1 magnitude of their Burgers vectors.
B、line direction is straight (edge) or curved (screw).
C、angle between Burgers vector and line direction.
D、None of above
10、Vacancy diffusion is usually interstitial one.
A、slower than
B、faster than
C、similar to
D、equal to
Chapter 5 Questions and Problems
1、Chapter 5 questions
Chapter 6 Mechanical properties
Test 3
1、Strain Hardening is also named as .
A、hot working;
B、metal forming;
C、work hardening
D、annealing
2、Yield strength is corresponding to the occurrence of deformation.
A、noticeable elastic;
B、noticeable visco-elastic;
C、noticeable plastic
D、noticeable thermal
3、In general, Brinell Hardness test is to measure the material’s hardness.
A、relatively softer
B、relatively harder
C、very hard
D、any
4、With plastic deformation, the increase of dislocation density will result in .
A、higher strength;
B、higher ductility;
C、higher toughness
D、higher grain-size
5、The finer the grains, the larger the , and .
A、strength, hardness, stiffness;
B、strength, hardness, brittleness;
C、strength, hardness, toughness;
D、hardness, brittleness, stiffness
6、Due to , alloys are usually than pure metals of the solvent.
A、solid solution strengthening, stronger;
B、solid solution strengthening, softer;
C、solid solution strengthening, tougher
D、plastic deformation, harder
7、Diffusion coefficient is with the increasing diffusion temperature.
A、exponentially increased;
B、linearly increased;
C、linearly decreased;
D、exponentially decreased
8、The driving force for steady-state diffusion is the __________.
A、concentration gradient
B、electric field
C、temperature
D、atomic oscillations
Chapter6 Questions and Problems
1、Chapter6 Questions and Problems
Chapter 7 Dislocations and strengthening mechanisms
Chapter 7 Questions and Problems
1、Chapter 7
Chapter 8 Phase diagram
Test 4
1、The phase diagram of Sn-Pb alloy is called .
A、Isomorphous phase diagram
B、Peritectic phase diagram
C、Eutectoid phase diagram
D、Eutectic phase diagram
2、A copper-nickel alloy is high-temperature heat treated; the diffusion of Cu into Ni and Ni into Cu regions is referred to as _____________________.
A、Vacancy diffusion
B、Interstitial diffusion
C、Bonding
D、Inter-diffusion
3、In a plain steel that contains 0.2 percentage carbon, we should expect: .
A、a eutectoid steel
B、a hypereutectoid steel
C、a 25% pearlite and 75% pro-eutectoid ferrite
D、a 75% pearlite and 25% pro-eutectoid ferrite
4、The maximum solubility of C in γ-austenite - solid solution is .
A、0.77
B、2.14
C、3.4
D、6.67
5、We have an annealed carbon steel which has hardness of 150HBS. Suppose we know the hardness of Pearlite is 200HBS and the hardness of Ferrite is 80HBS, determine the carbon amount of this steel.
A、0.45%
B、0.8%
C、1.2%
D、0.2%
6、The boundary above which only liquid phase exist is called _________.
A、liquidus
B、solidus
C、eutectic line
D、y-axis
7、Strength is increased by making dislocation motion .
A、fast
B、constant
C、difficult
D、stop
8、Heating the cold-worked metal progresses in three stages: .
A、recrystallization, recovery, grain growth;
B、recovery, recrystallization, grain growth;
C、recovery, crystallization, recrystallization;
D、recovery, crystallization, grain growth.
Chapter8 Questions and Problems
1、Chapter8 Questions and Problems
Chapter 9 Phase transformations
Test 5
1、Which of the following describes recrystallization?
A、Diffusion dependent with a change in phase composition
B、Diffusionless
C、Diffusion dependent with no change in phase composition
D、All of the above
2、Which of the following plane has the highest planar density for fcc.
A、(111)
B、(100)
C、(110)
D、(123)
3、During heat treatment of steel, austenite transforms into martensite by .
A、annealing
B、austenitizing
C、quenching
D、normalizing
4、In the as-quenched state, martensite is very hard and so brittle that a heat treatment known as must be accomplished sequently.
A、normalizing
B、annealing
C、tempering
D、austempering
5、The heat-treatable aluminum alloy can be strengthened by .
A、solution heat treating
B、precipitation heat treating
C、Both of above
D、None of above
6、Among the following typical transformations of austenite in steels, ____________transformation is diffusionless.
A、pearlitic
B、bainitic
C、martensitic
D、None of above
7、Engineering stress-strain curve and true stress-strain curve are equal up to .
A、Proportional limit
B、Elastic limit
C、Yeild point
D、Tensile strength point
8、Sterling silver (92.5%Ag/7.5%Cu) is an example of ___________.
A、Solid solution
B、Alloy
C、Defects
D、Catalyst
9、The point on a phase diagram where the maximum number of allowable phases are in equilibrium is .
A、eutectic point
B、liquidus point
C、solvus point
D、solidus point
Chapter 9 Questions and Problems
1、Chapter 9 Questions and Problems
Materials Science & Engineering Final Exam
Objective part
1、Which of the following electron configurations is for an inert gas?
A、1s22s22p63s23p6
B、1s22s22p63s2
C、1s22s22p63s23p64s1
D、1s22s22p63s23p63d24s2
2、What type(s) of bonding would be expected for brass (a copper–zinc alloy)?
A、Ionic bonding
B、Metallic bonding
C、Covalent bonding with some van der Waals bonding
D、van der Waals bonding
3、From the lead–tin phase diagram (Figure 9.8), which of the following phases/phase combinations is present for an alloy of composition 46 wt% Sn–54 wt% Pb that is at equilibrium at 44℃?
A、α
B、β+ liquid
C、α + β
D、α + β + liquid
4、Classify which of the following materials are ceramics?
A、Brass;
B、Magnesium oxide (MgO);
C、Polychloroprene;
D、Boron carbide (B4C)
Subjective part
1、For a brass alloy, the stress at which plastic deformation begins is 345 MPa (50,000 psi), and the modulus of elasticity is 103 GPa (15.0 * 10^6 psi). (a) What is the maximum load that can be applied to a specimen with a cross-sectional area of 130 mm2 (0.2 in.2) without plastic deformation? (b) If the original specimen length is 76 mm (3.0in.), what is the maximum length to which it can be stretched without causing plastic deformation?
2、A 65 wt% Ni–35 wt% Cu alloy is heated to a temperature within the ɑ+ liquid-phase region(Figure 2). If the composition of the a phase is 70 wt% Ni, determine (a) the temperature of the alloy (b) the composition of the liquid phase (c) the mass fractions of both phases
3、The microstructure of an iron–carbon alloy consists of proeutectoid cementite and pearlite; the mass fractions of these microconstituents are 0.11 and 0.89, respectively. Determine the concentration of carbon in this alloy.
4、Briefly explain the characteristics of cold working, and how to undo the effects of cold working.
5、Figure 10.40 shows the continuous-cooling transformation diagram for a 0.35 wt% C iron–carbon alloy. Make a copy of this figure, and then sketch and label continuous-cooling curves to yield the following microstructures: (a) Fine pearlite and proeutectoid ferrite (b) Martensite (c) Martensite and proeutectoid ferrite (d) Coarse pearlite and proeutectoid ferrite (e) Martensite, fine pearlite, and proeutectoid ferrite
6、Niobium (Nb) has an atomic radius of 0.1430 nm, an atomic weight 92.9g/mol and a density of 8.57 g/cm3. Determine whether it has an FCC or a BCC crystal structure.
学习通材料科学与工程基础（英文）
Materials science and engineering is an interdisciplinary field that focuses on the study of materials and their properties. It combines knowledge from physics, chemistry, and engineering to develop new materials and improve existing ones.
Course Overview
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Course Content
The course is divided into several modules:
- Introduction to Materials Science: This module provides an overview of the field and introduces the structure and properties of materials.
- Crystal Structure: This module covers the basic principles of crystal structure, including unit cells, crystal systems, and Miller indices.
- Defects in Crystals: This module explores the different types of defects that can occur in crystalline materials, such as vacancies, interstitials, and dislocations.
- Phase Diagrams: This module introduces the concept of phase diagrams and how they are used to predict the behavior of materials under different conditions.
- Metallic Materials: This module covers the properties and applications of metals, including their mechanical, electrical, and magnetic properties.
- Ceramic Materials: This module introduces ceramic materials and their properties, including their high temperature stability and hardness.
- Polymers: This module covers the properties and applications of polymers, including their mechanical, thermal, and electrical properties.
Assessment
The course includes several types of assessments to help students reinforce their understanding of the material:
- Quizzes: Short quizzes are included at the end of each module to test students' comprehension of the material.
- Assignments: Assignments are included throughout the course to help students apply their knowledge to real-world problems.
- Final Exam: A final exam is administered at the end of the course to assess students' overall understanding of the material.
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- Understand the basic principles of crystal structure, defects, and phase diagrams.
- Be familiar with the properties and applications of different types of materials, including metals, ceramics, and polymers.
- Be able to apply their knowledge to real-world problems in industry.
Conclusion
The materials science and engineering course on Learning Pass is an excellent resource for students interested in the field. It provides a comprehensive overview of the fundamental principles of materials science and their applications, and includes a variety of assessments to help students reinforce their understanding of the material.
