目前，信息、生物、先进制造等高新技术领域的微型化趋势极大地促进了微机电系统的发展。然而，表面和尺寸效应导致微机电系统产生了严重的粘着、摩擦与磨损问题。单晶硅基于其优良的物理、机械性能，已经作为典型的结构材料被广泛地应用于微机电系统中。NiTi合金具有形状记忆和超弹特性，是研制微机电系统传感器和驱动器的理想材料。因此，对它们微观磨损性能的研究，一方面可以丰富相关的纳米摩擦学的基础知识，其结果也可为高可靠性和长寿命微机电系统的研制提供理论指导。
本论文采用纳米压/划痕仪和原子力显微镜，分别对单晶硅和具有形状记忆效应的镍钛（SME NiTi）合金进行了划痕损伤研究。一方面，观察了单晶硅划痕损伤随载荷变化的整个过程，对比了单晶硅（100）与单晶硅（111）划痕损伤的异同，并讨论了针尖曲率半径对单晶硅划痕损伤的影响。另一方面，观察了SME NiTi合金划痕损伤随划痕循环次数的变化过程，表征了升温到100 oC后划痕损伤的恢复情况，讨论了界面摩擦力与犁沟摩擦力的变化与竞争关系，分析了NiTi合金往复划痕下的微观摩擦机理。本论文的主要结论如下：
1. 随载荷的增大，单晶硅（100）的划痕损伤先后经历了凸结构形成、凸起与凹槽并存和材料去除三个阶段。在低载下进行划痕实验时，硬度与弹性模量较小的单晶硅（100）上形成的凸起较单晶硅（111）上形成的凸起显著；小曲率半径的针尖在单晶硅（100）上产生较大的凸结构。
2. 单晶硅（100）的划痕损伤与其接触区的应力状态和环境气氛密切相关，表明其损伤初期凸结构的形成应当是摩擦化学与机械变形共同作用的结果。
3. 随着划痕循环次数的增加，SME NiTi合金划痕损伤的深度逐渐增大并趋于稳定。SME NiTi合金在常温下进行划痕实验时，其变形主要通过孪晶界的移动方式进行。加热过程中，由于发生了马氏体向奥氏体的转变，SME NiTi合金划痕损伤得到一定的恢复。
4. 随划痕循环次数的增加，SME NiTi合金划痕过程中的界面摩擦力逐渐增大并趋于稳定，而犁沟摩擦力和总摩擦力逐渐减小并趋于稳定。

Nowadays, the miniaturization trends in the areas of information, biotechnology and advanced manufacturing have greatly promoted the development of microelectromechanical systems (MEMS). However, the surface and size effects have induced the severe adhesion, friction and wear issues in MEMS. Based on their excellent physical and mechanical properties, monocrystalline silicon has been widely used in MEMS as typical structural material. Because of its shape memory effect (SME) and super elasticity (SE), NiTi alloy is the ideal candidate material for microsensors and microactuators. Therefore, the research on their microwear behaviors can not only improve our understanding on nanotribology, but also provide theoretical guidance for high reliability and long-life MEMS.
Based on nano-hardness/scratch tester and atomic force microscopy, the scratch behavior of silicon (100) and SME NiTi alloy was studied. Both the load effect and tip radii effect on the scratch behavior of silicon (100) were discussed. The number of scratch cycles effect on the damage behavior of SME NiTi alloy was investigated. The recovery of the scratch scar was characterized by heating to 100 oC. The competition of interface friction and plough friction was discussed. The micro-friction mechanism of SME NiTi alloy was analyzed under reciprocating scratches. The main conclusions can be summarized as follows:
1. With the increase in load, the scratch damage of silicon (100) has gone through three stages: the formation of upheaval, upheaval co-exist with groove and material removal. As the scratch experiment was performed at low load, the upheaval on silicon (100) was more remarkable than on silicon (111) because of its lower hardness and modulus of elasticity, and the upheaval was higher when the scratch tip’s radius is smaller.
2. The scratch damage of silicon (100) is closely related to the contact stress and the environment, which suggested that the initial formation of upheaval is induced by friction-chemical action and mechanical deformation.
3. The scratch depth of SME NiTi alloy is gradually increasing and tends to stabilize with the increase in the number of cycles. As the scratch experiment was conducted at room temperature, the deformation of SME NiTi is mainly due to the movement of twin boundaries. As the temperature increased above 100 oC, the deformation of SME NiTi alloy can be partly recovered due to the transformation from martensite to austenite.
4. With the increase in the number of cycles, the interface friction is gradually increasing and tends to stabilize. However, the plough friction and the total friction are gradually decreasing and tend to stabilize.