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材料导论

201is an elastomer having physical cross-links in network structure
202In comparison with PE,（）is or are correct
203A polymer is a macro-molecule formed by linking many small molecules together
204Degree of crystallinity indicates the fraction of crystalline structure or imperfections existing in polymers
205Semicrystalline polymers usually are transparent
206Rapid cooling of polymers could lead to order arrangement of chains for crystallization
207Viscoelasticity is a property unique to polymers such as plastics, elastomers and adhesives
208Increasing the molecular weight tends to raise the glass transition temperature
209Thermosets generally have better toughness or impact strength than thermoplastics
210Glass transition related closely to molecular motions
211The formation of cross-linked structures in synthetic rubbers is usually called vulcanization After vulcanization, there are still many carbon-carbon double- bonds in the molecular chains of natural rubber
212下面哪种材料不属于先进材料？
213材料可分为哪些类?
214研究材料时应关注以下哪个因素？
215不同材料里灌装的可乐喝起来一样，所以材料没区别。
216Property和Performance内涵一样。
217按照下面电子层的排列顺序，电子的能量逐渐升高。
218Fe的外围电子排布式是？
219核外电子排布的轨道能量，下面错误的是？
220Who set up the　periodic table?
221Which kind of bond in H2O?
222Which kind of bonding will be mainly existed in ceramics?
223The following elements are alkali metals
224Electrons in atoms would follow these principles
225The following bonds can be treated as weak bonds or secondary bonds
226The Pauli exclusion principle is the quantum mechanical principle which states that two or more identical fermions（particles with half-integer spin）can occupy the same quantum state within a quantum system simultaneously
227Atoms are made from a nucleus of protons and neutrons and a cloud of electrons
228Metal atoms become anions after they lost electrons
229When voltage is applied to an ionic material, entire ions must move to cause a current to flow, therefore, the electrical conductivity is very good
230What is the coordination number for FCC structure?
231How many atoms in HCP?
232For a ceramic compound, what are the characteristics of the component ions that determine the crystal structure?
233What are molecular structure in polymer?
234Which bond can be existed in polymer?
235The APF could not be same due to different crystal structure
236There are cations and anions in ceramics, therefore, the crystal could not be electrically neutral
237The chemical formula of a compound indicates the ratio of cations to anions, which must be stoichiometric
238The molecular weight of polymers is a fixed value
239A polymer chain is straight
240空位原子数的计算公式是哪个？
241Which of the following statement is incorrect
242Which of the following statement about Frankels defect is incorrect
243Which of the following statement about the Burgers vector is incorrect
244点缺陷包含的类型
245空位平衡浓度与哪些因素有关？
246Which of the following statements about solid solutions are correct
247下列属于热缺陷的有：
248Which of the following statements about dislocation are correct
249Which of the following statement is correct
250所有晶体都包含缺陷。
251晶体都呈现电中性。
252Defects do occur alone
253杂质原子加入金属中将会导致形成固溶体或者第二相。
254螺型位错位错线垂直于伯格斯矢量。
255刃型位错的位错线不一定是直线。
256在菲克第一定律中D 的含义是什么？
257渗碳层中碳浓度分布函数是？
258What are the factors that influence the diffusion?
259扩散机理可分为哪些？
260扩散系数与哪些因素有关？
261The vacancy is in the same direction as the atom
262空位扩散的速度要快于填隙扩散的速度。
263Nonsteady-state diffusion means that the diffusion particle concentration distribution does not change with time
264扩散系数只取决于晶体结构。
265Solid-state diffusion is a means of mass transport within solid materials by stepwise atomic motion
266韧度是衡量材料韧性大小的力学性能指标，是指材料断裂前吸收（）的能力。
267对于脆性材料,其抗压强度一般比抗拉强度（）。
268金属疲劳的判断依据是（）。
269常用的塑性判断依据是（）。
270The internal force concentration caused by internal force is called stress
271The stress distribution on the notch section is uniform
272形变强化是材料的一种特性， 是（）阶段产生的现象。
273以下哪个是增强技术遵循的准则?
274哪种晶界能有效阻止滑移并且增加材料强度?
275当杂质原子出现时，对滑移的抵抗力会（）。
276纯金属重结晶过程相比于合金重结晶过程会（）。
277晶核生长必须有以下哪些步骤?
278随着晶核生长，所有的晶界区域会（）。
279金属颗粒尺寸可能对下列哪些物质有影响?
280金属的位错密度会被以下哪些影响?
281重结晶过程中，力学性能会发生什么改变?
282The combination of the slip plane and the slip direction is called the slip system The less the slip system, the better the plasticity of the metal
283High yield strength is beneficial to material cold forming and welding performance improvement
284Plastic deformation is permanent
285A screw dislocation may be thought of as resulting from shear distortion
286For a screw, the dislocation line motion is parallel to the stress direction
287The grain boundaries usually do not come apart or open up
288During plastic deformation, slip or dislocation motion may not take place across a common grain boundary
289What is helpful in predicting phase transformation?
290Possibly the easiest type of binary phase diagram to understand and interpret is that which is characterized by the（）system
291The first step in the determination of phase compositions is to（）
292We can find（）single-phase regions in the copper-silver diagram
293In the BCC α ferrite, the maximum solubility is（）wt% at 727℃
294The maximum solubility of carbon in austenite, 214 wt%, occurs at（）℃
295The time necessary for the transformation to begin and then end depends on（）
296The thickness ratio of the ferrite and cementite layers in pearlite is approximately（）
297贝氏体的微观结构由（）和（）组成。
298自由能主要由哪些因素决定？
299For a binary system of known composition and temperature, that is at equilibrium, at least three kinds of information are available
300The form of iron-carbon phase can be divided into（）
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