材料概论ppt问题及其答案

1、说明：以下问题由老师所给的上课问题整理所得，其中Q -ADD是个人所加，答案并不完整且不完善，还望诸位共同合作Q11. Which glass is widely used in our ordinary life?More than 90% of the glass in us is based on oxides and in particular silica.2. Please give the main compositions of bio-glass? Calcium phosphate Silica3. How to prepare silicophosphate glasse

2、s?Sol-gel route4. Please list the general properties of glass? Lack of the periodic order of a crystal Metastability No fixed melting temperature IsotropyQ21. What is the role of C3S in Portland cement?2. How to delay the rapid setting of C3A2? Add some gypsum3. Please describe the properties of the

3、 reaction between Portland cement and water.4. Describe the abbreviations of SEM, TEM and XRD? SEM scanning electron microscope XRD X-ray diffractionQ31. Please list the properties of ceramics used in electrical applications. Semi-conducting, superconducting, piezoelectric, magnetic2. Please give th

4、e application of ceramics in medical. Repair and replacement of human hips, knees and other body parts Imaging system3. What is the wear resistance? The resistance of the removal of surface material4. What is the thermal shock? Which factors can affect the thermal shock resistance of materials? Ther

5、mal shock is a mechanism that can produce mechanical failure in materials. Factors: porosity, dispersions, noncrystal-linity, grain size, grain boundaries, pores and micro cracks.5. What are CVD and CVI? CVD is a process in which a mixture of gases is passed across a heated surface.CVI is somewhat r

6、elated to CVD, the major difference being that the deposition occurs insides a porous perform rather than only on a surface.Q41. What features do glasses have?2. 玻璃的组分可分为哪几类？3. 下面哪种方法较容易制备出含硅的磷酸盐玻璃 （ C ） (A) 高温熔融淬冷法 (B) 低温熔融淬冷法 (C) 溶胶-凝胶法 (D) 化学气相法Q51. What factors will affect the refractive index o

7、f glasses?They are the wavelength of light, the density, temperature, thermal history, stress and composition of the glass.2. Please list the major techniques for glasses formation？ They are blowing, compression, drawing, floating method, rolling, and casting, respectively.3. What is the nature of g

8、lass lacking electronic conductivity?Without free electron movement.4. Please give examples about the application of glass. For example: application in architecture, in anti-solar, in fiber optics5. Please list the recent topics about glass in optoelectronics field.Blue and green light sources, host

9、-guest stems for non-linear optics, up-conversion glasses, optical switches, optical fibers.Q61. Please define brass and bronze? Brass: The copper-zinc alloys Bronze: The copper-tin alloys2. Which structure do zinc and copper adapt? Zinc: hexagonal-close-packed structure Copper: face-centered cubic

10、structure3. Please list three Refractory Metals. Chromium Tantalum Vanadium etc4. Please give the characteristics of titanium? Light weight Silvery color Blue grinding sparksQ71. Please list several chemical processes for powder preparation. (1) a cold step, in which the ceramic part is formed or sh

11、aped into a green part or preform (2) a hot step, in which the green compact is first subjected to heat to dry up any liquid phase formed during the processing and then subjected to higher heating, known as firing, sintering, or densification.2. What is vapor process for advanced ceramics and give s

12、ome examples? Vapor process, including heating a solid substance to a temperature that transforms the solid into a vapor, which is then deposited onto a surface. Some examples: PVD, CVD, CVI, MBE, LPE etc.3. Please describe the mechanical properties. (我个人认为这里所指的是陶瓷的机械性能) Good in compressionVery high

13、 hardness Great stiffness Brittleness etc4. List some applications of ceramics? Refractories Use in the construction industry Lighting electrical Electrical application CommunicationMedicalEnvironmental and space applicationQ81. What is a key factor for preparing glasses?Cooling temperature2. Please

14、 give explanations about following scheme?Figure 4.2 Variation of volume of a simple glass forming melt along with that of the crystal. The cooling rate for curve a is higher than that for curve b (schematic). P1443. Please list the major techniques for glasses formation？ 4. 例举玻璃的结构学说? Continues ran

15、dom network model Random close packing model5. How to decide whether the glass is amorphous? P136 6. What is the main usage for chalcogenide glasses? Infrared window7. What is the role of silica in glasses? Glass forming material8. What chemical types do glasses formation occurs?Q91.试计算体心立方铁受热而变为面心立

16、方铁时出现的体积变化。在转变温度下,体心立方铁的点阵参数是 0.2863nm，而面心立方铁的点阵参数是0.3591nm。 体心立方晶胞的体积= (ab)3=(0.2863)3=2.3467×10-4面心立方晶胞的体积= (af)3=(0.3591)3=4.6307×10-4但是面心立方晶胞含有4个原子，而体心立方晶胞只含有2个原子。两个体心立方晶胞才含有4个原子，总体积为2 ×2.3467×10-4=4.6934×10-4体积变化= (4.6934-4.6307)/4.6934=-1.34%这表明铁在加热时出现收缩 Q-ADD1. What is Ceramic compounds? Inorganic compounds made by heating clay or other mineral matter to a high temperature at which they partially melt and bond together. 2. Please give some traditional ceramics? 3. What are differences between traditional Ceramic and advanced ceramics? A