表面工程学知识（Knowledge of surface engineering）.doc

表面工程学知识（Knowledge of surface engineering） The ideal surface: you can imagine the insertion of a plane for the infinite crystal, the surface is divided into two parts formed after, and that in a semi infinite crystal atoms and electron density are the same with the original infinite crystal. Clean surface: Although the atomic structure of the surface of the material is periodically different from that of the body, if the chemical composition is the same as in the body. Clean surface: the surface of a component after cleaning. Typical solid interface: 1. solid phase differences in grain size and microstructure based on the formation of the interface, when the external force acting on the metal surface, the surface at a distance of a few microns range, the microstructure has changed greatly; 2. of the surface of solid tissue or crystal structure based on the difference of formation, typical of this interface is there is a big difference in micro the microstructure and composition of the two phases, but no significant difference between the 3. macro components; solid phase difference form based on the macroscopic composition interface, metallurgical bonding interface diffusion bonding interface, epitaxial growth, chemical bonding interface bonding interface, molecular bonding interface, mechanical interface. Wear principle: friction is independent of contact area; proportional to normal load; independent of sliding speed. Categories: dry friction, boundary lubrication, friction, fluid lubrication, friction, and rolling friction. Adhesion wear, abrasive wear, fatigue wear and corrosion wear Ways to improve the wear resistance of parts: the internal structure design reasonable design a project structure, 1. products must be reasonable design and deal with the importance of 2. parts maintenance difficulty, product cost, characteristics, environmental characteristics of the first comprehensive analysis; two, selection of machine parts wear forecast, analysis and wear resist