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1、Reference answer to the reviewed questions（仅供参考，不当之处请自行改正）(一) Give examples of recent developments in materials science and engineering that haveaffected technologies such as information,transportation,production,medical and entertainment.For example,the advances in semiconductor and liquid crystal
2、(LCD) technology lead to evolutions of telephones and watches.Also, advances in materials and process technology have provided for smaller, lighter, and even flexible batteries that last longer, thus allowing greater functions in cell phones and watches, as well as for computers and other devices. T
3、hirdly, Synthetic polymer, polyurethane plastic （聚氨酯塑料）wheels on skates give improved traction, shock absorption and lighter weight over the older steel. At last,.advances in materials technology brought on new containers made of two-piece aluminum and steel cans and barrier packages made of laminat
4、ed composites of plastic, aluminum, and paper. These new containers are light-weight, will not break, and offer long shelf life for their contents.(二) Give one of ceramic material classifications.For example,ceramis materials can be classified into traditional ceramis materials and advanced ceramis
5、materials.The former one is based primarily on natural raw materials of clay and silicates,including clay products,glass,cement.The latter one is artifical raw materials, exibiting specialized properties and requiring more sophisticated processing.It includes structural ceramic(wear parts, biocerami
6、cs, cutting tools, and engine components) ,electrical ceramic(capacitors, insulators, substrates, integrated circuit packages, piezoelectrics, magnets and superconductors) and coatings ceramic(engine components, cutting tools, and industrial wear parts) .(三) Give one example of application of the te
7、trahedron of materials science and engineering.For example,the following is Application of the tetrahedron of materials science and engineering to sheet steels for automotive chassis.(车架；底盘) (四) Describe the structures of silica tetrahedron（硅氧四面体）The silica tetrahedron has an internal arrangement co
8、nsisting of pyramid（锥形）units. Four large oxygen (O) atoms surround each smaller silicon (Si) atom. The silicon atoms occupy（占据） the openings (interstitials，间隙)， between the oxygen atoms and share four valence electrons （价电子）with the oxygen atoms through covalent bonding. （共价键）(五) Give some typical p
9、roperties of silica tetrahedron（硅氧四面体）Porosity and density（孔和密度）、wear resistance（耐磨性）、stress concentration and fracture toughness（应力集中和断裂韧度）、thermal shock resistance（耐热震性）、emissivity(辐射系数)、brittle fracture、flexural strength（挠曲强度）(六) Types of defects in crystals,what is Schotky Defect and Frenkel Def
10、ect?Point defects, line defects,surface defects.Schotky Defect means anion vacancy and cation vacancy（阴阳离子空位）. Frenkel Defect refers to vacancy and interstitial pair.(离子空位和间隙离子对)。(七) Process flow diagram(工序流程图) for ceramic products manufacturing.The basic steps include raw material procurement（原材料生产
11、）, beneficiation（改性）, mixing（混合）, forming（成型）, green machining（生坯加工）, drying, presinter thermal processing,（初步烧结热处理） glazing（上釉），firing, final processing, and packaging. (八) The purpose of comminution(粉碎；捣碎) during raw-materials benefication.The purpose of comminution is to liberate（释放）impurities, b
12、reak up aggregates（骨料）, modify particle morphology（形态） and size distribution（粒径分布）, facilitate（促进） mixing and forming, and produce a more reactive material for firing. (九) How to remove bubbles from glass melts(玻璃熔体)?Bubbles are eliminated during melting by a process known as fining（纯化）.Fining can b
13、e achieved by increasing the temperature of the molten glass by about 150C to reduce its viscosity(粘性) From Stokes law（斯托克斯定律） (or by comparing the rise of bubbles in Cola versus liquid soap，肥皂溶液) we know that the drift velocity（漂移速度） of the bubbles toward the surface of the melt is increased as the
14、 viscosity of the melt is decreased；Fining is also traditionally achieved by adding fining agents,（纯化剂） such as Na2SO4 or NaCl, to the melt at the end of the melting process. The fining agent decomposes as shown in Eq. produce a large quantity of gas bubbles, which coalesce with existing bubbles, in
15、creasing their volume and hence taking them to the surface faster.(十) The general properties of refractory（耐火材料） Withstand high temperature without melting or decomposing；Remain unreactive and inert （惰性的）when exposed to severe environment。（恶劣环境）(十一) Give process parameters(参数；参量) that affect ceramic
16、 firing(陶瓷烧制).How do these parameters affect firing?Process parameters that affect firing ：firing temperature、time、pressure、atmosphere;Temperature:Time:Short firing time results in a product that is porous （多孔的）and has a low density;Intermediate firing time results in fine-grained（细粒的）, high-strength products;Long firing times result in a coarse-grained （粗粒的）products that are more cre
