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Gear tooth profile modification can be featured to improve working stability of gear equipments, abate noise and vibration, enhance loading ability and prolong usage life of the gears. Fine forged spur bevel gear are formed with molds, so it is economical to modify the gears by means of modifying mold cavity. Whether the modified gears can be separated from the mold with easiness is proposed to be the basic criterion of gear tooth profile modification design. Near the big ends and tooth roots is mainly the area which affects demolding after modification. According to the modified gear configuration, mathematical model is built to calculate the demolding check at any modification points on the fine forged spur bevel gear profile. And a corresponding program is developed, which is the main tool for the gear tooth profile modification design, and practical calculation has carried out.

Based on the gear geometry theory and the normal meshing motion equation of gear pairs， changes of meshing points and angles are analyzed and the effect of tooth trace modification on gear pair meshing movement is discussed. It is concluded that chemical milling can effect tooth trace involute modification of fine-forged spur bevel gear, improve its surface quality and dimensional precision and therefore prolong its service life.

The study reports a new surface formation technology during manufacturing process of parallel indexing cam mechanism, ion beam sputtering deposition, in which the operation temperature can be controlled below the limitation of phases exchanging or at room temperature. Phase exchanging deformation can be avoided and the shape accuracy and dimension accuracy can be improved compared with surface quenching process. The microstructure and properties of TiAlN/AlN composite film deposited on the profile surface of cam (made of 45 steel) by ion beam sputtering deposition were discussed. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM) analysis has been used to characterize film’s microstructure and properties. The micro-hardness and adherence grade were tested.

The microstructure and surface micromorphology of ZnSe single crystals grown directly from zinc and selenium have been investigated using rotation orientation x-ray diffraction (RO-XRD), atomic force microscope (AFM) and field emission scanning electron microscope (FE-SEM). The ZnSe samples exhibit only the surface leaning to (111) singular face by the angle of 3.13°, which is the buildup of two-dimensional dendritic crystal layers. Numerous nuclei and cavities distribute unevenly across the crystal surface, governing the formation of growth layer, while the dendritic crystal layers develop rapidly by margining the smaller nuclei. The formation of these microstructure and micromorphology on the surface of ZnSe crystals depends on the surface supersaturation and the growth parameters.