義守大學 93 學年度博士班入學招生考試試題 系所別 材料科學與工程學系 考試日期 93/07/03 考試科目 材料科學 總頁數 1 ※ 此為試題卷,考生請於答案卷上作答。 ※ 本考科可使用計算機、不可使用字典。 1. 2. 3. 4. 5. 6. 7. 8. Can AZ91D(a Magnesium alloy) be forged? Why? What are the differences between embryo and nuclei by solidification of pure metals? (a) Cite the reasons why ferrous alloys are used so extensively? And (b) cite the principal disadvantage of ferrous alloys and the way of overcoming this disadvantage. What are the principles for metallographical investigation of metals? Write down in details the defect chemistry equations of a Ti site acceptor and Ba site donor doping in Barium titanate, define all terms used in the equations. (A) What are the two characteristics of ions that determine the resulting ceramic crystal structure when they are combined? (B) MgO has the “rock salt” or “Sodium chloride” structure. (1) Sketch the (100) plane of the unit cell of MgO, showing the atomic arrangement. Label the anions and cations. (2) Given the ionic radii of magnesium and oxygen are as follows: Ionic radius of Mg+2 = 0.072 nm and ionic radius of O-2 = 0.140 nm, calaulate the unit cell dimension, a, of MgO. Determine the heat of vaporization of Zinc at 1000 K. The vapor pressure over the liquid Zinc is presented by; Log PZn (mmHg) = -6620/T – 1.255 Log T + 12.34 If the isobaric thermal expansivity and the isothermal compressibility are defined as VTα 2 1 ⎛ ∂V ⎞ −1 ⎛ ∂V ⎞ , where CP and CV ⎟ and β = ⎟ . Prove that CP – CV = ⎜ ⎜ β V ⎝ ∂T ⎠ P V ⎝ ∂P ⎠T are the molar heat capacities under constant pressure and constant volume respectively. α = An n-type Si wafer has been doped uniformly with 1016 antimony (Sb) atoms per cm3. Calculate the position of the Fermi energy with respect to the Fermi energy, EFi, in intrinsic Si. The above n-type Si sample is further doped with 2x1017 boron atoms per cm3. Calculate the position of the Fermi energy with respect to the Fermi energy, EFi, in intrinsic Si, and hence with respect to the Fermi energy in the n-type case above. 10. Please brief describe scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) theory and applications in material analysis and give an example to combine them together in materials study? 9. 第1頁