中国大学Engineering Materials期末答案(mooc2023课后作业答案)
29 min read中国大学Engineering Materials期末答案(mooc2023课后作业答案)
Mechanical Properties of Engineering Materials
1、中国作业In the following hardness measurement method,大学答案答案 the diamond head is used for ( ).
A、HV
B、期末HRC
C、课后HB
D、中国作业HRA
2、大学答案答案The期末 following statement about fatigue is true ( ).
A、The课后 stress of fatigue is higher than the yield strength of static load.
B、Obvious plastic deformation can be observed at fatigue fracture.
C、中国作业Fatigue fracture can be divided into fatigue source,大学答案答案 bright area, rough area.
D、The期末 occurrence of fatigue fracture is premonitory and is called brittle fracture.
3、What's true about the fracture is 课后that ( ).
A、Brittle material fracture fibrous.
B、中国作业Ductile materials have no obvious plastic deformation before fracture.
C、大学答案答案The期末 fracture of the ductile material is crystalline and shiny.
D、The fracture of brittle materials is crystalline or porcelain.
4、KIC is the index of fracture toughness of type I crack. The following statement is correct ( ).
A、when KⅠ < KⅠC, crack began to expand, brittle fracture.
B、when KⅠ > KⅠC, crack extension occurs brittle fracture of instability.
C、when KⅠ = KⅠC, extension began to occur.
D、when KⅠ = 1/2KⅠC, crack extension.
5、Improving lubrication conditions and enhancing the stability of the oxide film are targeted at that type of wear ( ).
A、abrasive wear
B、contact fatigue wear
C、adhesive wear
D、corrosion and wear
2 Microstructure of Engineering Materials
Microstructure of Engineering Materials
1、The number of atoms contained in a dense cubic cell is ( ).
A、2
B、3
C、6
D、8
2、In the crystals of the following substances, the substance with ionic bonds is ( ).
A、SO2
B、SiO2
C、NaCl
D、H2O
3、( ) are the most basic and independent components in the alloy.
A、component
B、alloy
C、phase
D、solid solution
4、Among the following defects, ( ) belongs to the point defect.
A、positive edge dislocation
B、Frenkel defect
C、negative edge dislocation
D、screw dislocation
5、In the following objects, ( ) belongs to crystal.
A、ice
B、glass
C、rosin
D、asphalt
3 Solidification and Crystallization of Engineering Materials
Solidification and Crystallization of Engineering Materials
1、For a given alloy at a certain temperature, the composition of the two equilibrium phases only needs to be a parallel line of the abscissa of the composition at that ( ). The intersection of the parallel line and the curves in the phase diagram corresponds to the composition of the two equilibrium phases.
A、Temperature
B、Quality
C、Quality score
D、Molar mass
2、Generally, when the solid solution is crystallized in equilibrium, the composition of the liquid phase changes along the ( ) line and the composition of the solid phase changes along the solidus line, and finally a solid solution with uniform composition is obtained.
A、Solid phase
B、Liquidus
C、Solid-liquid interface
D、Above the liquid surface
3、Taking the binary phase diagram of Pb-Sn alloy as an example, there are ( ) single phase regions.
A、Two
B、Three
C、Four
D、Five
4、Peritectic phase diagram: two groups of elements can ( ) in liquid state , but in the solid state, it can only be dissolved in a limited amount and has a phase diagram of peritectic transition.
A、Infinite dissolution
B、Limited dissolution
C、Dissolve with each other
D、Dissolve half
5、The alloy phase diagram is an important diagram reflecting the equilibrium crystallization characteristics of the alloy, as well as the relationship between the alloy composition and the balance structure, and the performance of the alloy mainly depends on the composition and structure of the alloy, so the performance of the alloy can be qualitatively judged according to the ( ).
A、Composition of alloy
B、Structure of alloy
C、Phase diagrams
D、Composition and structure of alloy
4 Plastic Deformation and Recrystallization of Metals
Plastic Deformation and Recrystallization of Metals
1、When a solid is subjected to external force, it will ( ) .
A、change in shape
B、change in property
C、slide
D、occur plastic deformation
2、The plastic deformation of polycrystal is much more complicated than that of monocrystal mainly because of ( ) .
A、impurity atoms
B、lattice
C、grain boundary
D、twining
3、( ) is an important means of strengthening metal materials.
A、elastic deformation
B、plastic deformation
C、stretching
D、fibrous structure
4、Plastic deformation can break the crystal grains of metal materials and ( ).
A、increase the toughness
B、decrease the dislocation density
C、increase the plasticity
D、increase the dislocation density
5、If the heating temperature is increased after recrystallization, ( ) will take place.
A、secondary recrystallization
B、fine grain strengthening
C、work hardening
D、solid solution strengthening
5 Iron-carbon Alloys
Iron-carbon Alloys
1、During the crystallization process of pure iron from liquid cooling to room temperature, the crystal structure of pure iron will change from body centered cubic to ( ).
A、Face centered cubic
B、Hexagonal close-packed
C、Complex cubic
D、Body centered cubic
2、Pearlite is a kind of ( ).
A、Metal compound
B、Solid solution
C、Mechanical mixture
D、Chemical compound
3、The solid-phase process in which two components are fixed is generated from the solid phase of a certain component at a certain temperature is ( ).
A、Eutectoid reaction
B、Peritectic reaction
C、Eutectic reaction
D、Homogenization reaction
4、Among the common impurity elements in carbon steel, ( ) element dissolved in ferrite can cause cold short.
A、P
B、Si
C、Mn
D、S
5、The average chromium content in GCr15 steel is ( ).
A、0.015
B、15
C、1.5
D、0.15
6 Heat Treatment of Steels
Heat Treatment of Steels
1、Competely annealing is mainly used for ( ).
A、hypoeutectoid steel
B、eutectoid steel
C、hypereutectoid steel
D、all steel
2、In continuous cooling transformation products of eutectoid steel, the impossible structure is ( ).
A、P
B、S
C、B
D、M
3、The normalizing temperature of subeutectoid steel is generally ( ).
A、Acl+30-50°C
B、Accm+30-50°C
C、Ac3+30-50°C
D、Ar3+30-50℃
4、Mild steel is often made for easy cutting after ( ).
A、complete annealing
B、normalizing
C、spherification annealing
D、incomplete annealing
5、In following temperatures ( ) is not in the range of high, medium and low temperature tempering temperatures of steel.
A、200℃
B、350℃
C、400℃
D、500℃
7 Alloy Steels
Alloy Steels
1、Boron is added to structural steel to increase its ( ).
A、tempering stability
B、toughness
C、hardenability
D、hardening capacity
2、The main purpose of adding Ti to steel is ( ).
A、Refining grain
B、Improve tempering stability
C、Reinforced ferrite
D、Increasing hardenability
3、The heat treatment of spring steel is treated by ( ).
A、quenching and low tempering
B、quenching and tempering
C、quenching and middle tempering
D、quenching and high tempering
4、The purpose of solid solution treatment of 1Cr18Ni9Ti austenitic stainless steel is ( ).
A、Single austenitic structure is obtained to improve corrosion resistance and prevent intergranular corrosion.
B、Obtain a single martensite structure to improve hardness and wear resistance.
C、Reduce the hardness, easy cutting.
D、Improves plasticity and toughness.
5、( ) is the alloy tool steel.
A、1Cr18Ni9Ti
B、9CrSi
C、20Cr
D、T12
8 Cast Iron
Cast Iron
1、Which cast iron has flake graphite? ( )
A、nodular cast iron
B、malleable cast iron
C、gray cast iron
D、vermicular cast iron
2、Which cast iron has flocculent graphite? ( )
A、gray cast iron
B、malleable cast iron
C、nodular cast iron
D、vermicular cast iron
3、Which following one is wrong ? ( )
A、Gray cast iron has high strength.
B、Gray cast iron has good wear resistance.
C、Gray cast iron has good cutting performance.
D、Gray cast iron has good casting property.
4、Which one is not a factor affecting graphitization of cast iron? ( )
A、temperature of melt
B、composition of melt
C、cooling rate of melt
D、heating rate of alloy
5、Which one is not right about the alloy elements in gray cast iron? ( )
A、Aluminum can contribute to forming graphite.
B、Nickel is harmful to the graphitization.
C、Tungsten is harmful to the graphitization.
D、Cobalt is helpful to the graphitization.
Engineering Materials
Engineering Materials
1、KIC is the index of fracture toughness of type I crack, which following statement is correct ( ).
A、when KⅠ < KⅠC, crack began to expand, brittle fracture.
B、when KⅠ > KⅠC, crack extension occurs brittle fracture of instability.
C、when KⅠ = KⅠC extension began to occur.
D、when KⅠ = 1/2KⅠC, crack extension.
2、The number of atoms contained in a dense cubic cell is ( ).
A、2
B、3
C、6
D、8
3、In the crystals of the following substances, the substance with ionic bonds is ( ).
A、SO2
B、SiO2
C、NaCl
D、H2O
4、Generally, when the solid solution is crystallized in equilibrium, the composition of the liquid phase changes along the ( ) line and the composition of the solid phase changes along the solidus line, and finally a solid solution with uniform composition is obtained.
A、Solid phase
B、Liquidus
C、Solid-liquid interface
D、Above the liquid surface
5、Taking the binary phase diagram of Pb-Sn alloy as an example, there are ( ) single phase regions.
A、2
B、3
C、4
D、5
6、When a solid is subjected to external force, it will ( ).
A、change in shape
B、change in property
C、slide
D、occur plastic deformation
7、Improving lubrication conditions and enhancing the stability of the oxide film are targeted at that type of wear ( ).
A、abrasive wear
B、contact fatigue wear
C、adhesive wear
D、corrosion and wear
8、During the crystallization process of pure iron from liquid cooling to room temperature, the crystal structure of pure iron will change from body centered cubic to ( ).
A、Face centered cubic
B、Hexagonal close-packed
C、Complex cubic
D、Body centered cubic
9、The plastic deformation of polycrystal is much more complicated than that of monocrystal mainly because of ( ).
A、impurity atoms
B、lattice
C、grain boundary
D、twining
10、Among the following defects, ( ) belongs to the point defect.
A、positive edge dislocation
B、Frenkel defect
C、negative edge dislocation
D、screw dislocation
11、earlite is a kind of ( ).
A、Metal compound
B、Solid solution
C、Mechanical mixture
D、Chemical compound
12、Boron is added to structural steel to increase its ( ).
A、tempering stability
B、toughness
C、hardenability
D、hardening capacity
13、Peritectic phase diagram: two groups of elements can ( ) in liquid state , but in the solid state, it can only be dissolved in a limited amount and has a phase diagram of peritectic transition.
A、Infinite dissolution
B、Limited dissolution
C、Dissolve with each other
D、Dissolve half
14、Competely annealing is mainly used for ( ).
A、hypoeutectoid steel
B、eutectoid steel
C、hypereutectoid steel
D、all steel
15、Plastic deformation can break the crystal grains of metal materials and ( ).
A、increase the toughness
B、decrease the dislocation density
C、increase the plasticity
D、increase the dislocation density
16、In the following hardness measurement method, the diamond head is used for ( ).
A、HV
B、HRC
C、HB
D、HRA
17、The normalizing temperature of subeutectoid steel is generally ( ).
A、Acl+30-50°C
B、Accm+30-50°C
C、Ac3+30-50°C
D、Ar3+30-50℃
18、Among the common impurity elements in carbon steel, ( ) element dissolved in ferrite can cause cold short.
A、P
B、Si
C、Mn
D、S
19、Mild steel is often made for easy cutting after ( ).
A、complete annealing
B、normalizing
C、spherification annealing
D、incomplete annealing
20、If the heating temperature is increased after recrystallization, ( ) will take place.
A、secondary recrystallization
B、fine grain strengthening
C、work hardening
D、solid solution strengthening
学习通Engineering Materials
Engineering Materials是Engineering学科领域的一门重要课程，其主要涵盖了材料力学、材料热力学、材料物理等多个方面的知识点，为工程设计与制造领域提供了必要的理论支持。而在学习这门课程时，我们可以通过学习通平台提供的课程资源来深入了解Engineering Materials的相关知识点。
课程内容
Engineering Materials的课程内容主要包括以下几个方面：
- 材料分类与性能
- 晶体结构与缺陷
- 力学性能
- 热力学性能
- 电磁性能
- 物理性能
通过这些学习内容的掌握，我们可以深入了解不同材料的特性，进而在工程设计与制造中选择合适的材料，提高产品的性能和质量。
课程教材
学习通Engineering Materials的教材主要为《Engineering Materials》一书，该书由英国谢菲尔德大学的David R.H.Jones和Michael F.Ashby两位教授共同编写，是Engineering Materials领域的经典教材之一。
该书分为14章，每章都涵盖了具体的知识点，并提供了相关的例题和练习题，方便学生进行巩固及检验自己的掌握程度。此外，该书还提供了大量的实例，使得学生能够更好地理解材料性能与应用。
课程考核
Engineering Materials的考核方式主要包括平时成绩和期末考试两部分。
平时成绩占总成绩的30%，主要包括课堂表现、作业、实验等，旨在评估学生对材料性能和应用的理解和掌握情况。期末考试占总成绩的70%，采用闭卷考试的形式，主要测试学生对材料性能和应用的综合运用能力。
学习心得
对于Engineering Materials这门课程，我认为需要掌握的知识点较多，需要花费大量的时间和精力来学习和练习。但是，通过系统地学习和巩固，我逐渐深入了解了不同材料的性能和应用，掌握了选择和设计合适材料的方法和技巧。
此外，在学习Engineering Materials时，我还参与了一些实验课程，通过实践来加深对材料性能和应用的理解和掌握。这些实验课程涉及到材料的强度、硬度、韧性等多个方面的测试，让我更加直观地感受和理解了材料的性能。
综上所述，Engineering Materials是一门具有重要意义的课程，能够为工程设计和制造领域提供必要的理论支持。在学习这门课程时，需要坚持学习和练习，并注重实践，才能更好地掌握相关的知识和技能。
中国大学Engineering Materials
Engineering Materials是中国大学中的一个重要专业，涉及材料科学、物理、化学、机械学等领域。该专业旨在培养学生成为材料领域的专业人才，他们能够在各种工程领域中独立工作。
专业设置
在中国大学中，Engineering Materials专业通常设置在工科类学院中。该专业包括本科、硕士、博士三个层次。
本科
本科专业通常为4年制，主要课程包括材料科学基础、材料化学、材料测试与分析、材料工程等。学生将学习各种材料的基本性质、生产和加工工艺，以及材料在机械、电子等领域中的应用。
硕士
硕士专业为2-3年制，主要关注材料科学及相关领域的深入研究。学生将深入学习材料的微观结构、性能、加工及应用等方面的知识。
博士
博士专业通常为3-5年制，注重深入研究材料领域的前沿问题，通过开展科研工作，为该领域的发展做出贡献。
就业前景
随着科技的不断进步，Engineering Materials专业得到了越来越多的关注。毕业生往往可以选择在国内外的大型企业、科研机构或高校从事相关工作。工作内容包括材料研究与分析、材料应用开发、材料设计等。工作职位包括材料工程师、研究员、教授等。
学术研究
Engineering Materials专业在材料科学和工程领域具有重要的研究价值。该专业的研究方向包括材料合成与制备、材料物理与化学性质、材料应用和性能等领域。在国内外，该领域的研究在汽车、建筑、电子等领域发挥着重要作用。
学术成果
Engineering Materials专业的教授和研究人员通常会在相关学术期刊上发表研究论文。他们的研究成果被广泛应用于各种工程领域，例如汽车制造、建筑和能源等。
总结
Engineering Materials专业是中国大学中一个重要的专业，在各种工程领域中发挥着重要作用。该专业的学生将学习材料科学、物理、化学、工程等领域的知识，并能够在相关领域中进行独立研究和开发。
