第一部分填空题(10个空共10分,每空一分) 1.材料科学与工程有四个基本要素,它们分别是:使用性能、材料的性质、和 2.材料性质的表述包括、物理性质和化学性质

1.2 Atomic bonding Bonding forces and energies FF net force attractive force repulsive force

2.5 Indices of crystal planes and directions I What's crystal planes anddirect ions? The atomic planes anddirections passing through the crystal arecalled(crystal) planes and directionsrespectively

4. Rule for elongation or reduction of R D All R.D. in the region where K1 and K2 makes an obtuse(acute) angle will increase (reduce) its length after twinning

2.7 Some Important Crystallographic Formulas 1. Zone and zone equation All Planes parellel to common axis [uvw] constitute a (crystal) zone, the [u v w] zone. If (h k l) belongs to zone [u v w], then hukv+=0 2.ifhuk+hw=0,then[uvw] lies in(hk) 3. For cubic crystals, [h (h k)

1. Sing le crystal ver sus po l crystal 1. For single crystals there is only one type of structure with same orientation Single crystals is characterized by anisotropy 2. Polycrystal consists of a lot of grain, small single crystals, With same structure but different orientations. These small single crystals are called grains. The boundaries between them are called grain boundaries

Paulings three rules governing the structure of ionic compounds 1. Anion Coordination polyhedron rule Each cation is surrounded by an anion polyhedron, the distance between anion and cation is r=rt tr, while the cn depends on rt/r

1. Deformation process of polycrystalline materials Deformation process of industrial material consists of three stages Elastic. which is reversible

1. The cause of rotation: Due to constraints, or boundary conditions imposed on the crystal. ll. The rule of rotation:

Edge dislocation 1. Slip (glide) Dislocation motion vs. atom movement. Direction:l⊥讠 Plane:lb(l× Dislocation motion vs. crystal movement. → crystal movement→(dislocation motion)