Papers by Author: Gui Cheng Wang

Abstract: With the development of high-speed machining technology, new technical requirements have been put forward for the clamping of high-speed cutting tools. The traditional clamping methods can not meet the needs of high-speed machining. In this paper, the comprehensive performance of high-speed chucks is systematically compared and analyzed, and the characteristics and main application areas of various high-speed chucks are sorted out, which provides a theoretical basis for scientific and rational selection of chucks.

Abstract: Based on the fundamental theory of axial vibration drilling, the influence of vibration drilling on the feed-exit burr has been analyzed. The result shows that, due to axial vibration,vibration drilling has some unique characteristics, such as variable-thickness cutting and impulse cutting,which not only improve the chip-breaking conditions and working angle of the drill,but reduce the thrust force.Therefore, the plastic deformation of workpiece material and the exit burr are restrained and decreased effectively.

Abstract: The grind-hardening test of 42CrMo steel was carried out on a forming grinding machine. The macrostructure, microstructures, micro-hardness and the depth of the hardened layer were measured and analyzed by optical micro-scope, scanning electron microscope and digital micro-hardness tester. The influences of original microstructure on the grind-hardened layer of 42CrMo steel were studied. The results show that the acicular martensite and a small amount of undissolved carbide appear in the surface layer, and slightly coarse martensite and a small amount of undissolved carbide appear in the middle layer of the completely hardened zone. Microstructure of the transitional zone varies with original structure. The microstructures and micro-hardness of the completely hardened zone have no obvious change under different original organizations, and the micro-hardness is 620HV0.5-700HV0.5. However, the distance from the slightly coarse martensite and the depth of the hardened layer increase with the uniformity improvement of the original microstructure.

Abstract: Due to the high precision and strong molding capacity, micro-milling plays an important role in the field of micro-machining. The components machined in micro-machining is smaller than conventional components, and sometimes the generated burrs are as large as the feature size of components, so the study of micro burr control is very important. In the reseach, cutting-direction burrs are based on the traditional milling characteristics, also combined with the characteristics of micro-milling. The experimental data verify the correctness of the model well, so it provides theoretical guidance for the burrs control in micro-milling.

Abstract: Tooling system for high-speed machining is one of the key components of high-end CNC machine , its stability and reliability directly affects the quality and performance of the machine. Based on the finite element method, developing a 3D finite model of high-speed machining tool system, studying on the stability of the high Speed machining tool from the natural frequency by the method of modal analysis. Analysis the amount of the overhang and clamping of the tooling , different shank taper interference fit and under different speed conditions, which affects the natural frequency of high-speed machining tool system. Proposed to the approach of improving system stability, which also provides a theoretical basis for the development of new high-speed machining tool system.

Abstract: Cutting-direction burr/fracture is one of the important factors that influence the edge quality and performance of precision parts. The formation of negative shear zone decisions the edge quality of workpiece. A finite element model has been established to investigate the mechanism of negative formation in machining H64 brass. The negative shear zone formation process is simulated with rigid-plastic nonlinear finite element method. The cutting direction burr forms when the stress of principal shear zone great than it in negative, the cutting direction fracture forms when the stress of principal shear zone less than it in negative and there is a crack in the area near the tool tip and grow along the negative shear zone .

Abstract: A three-dimensional model of micro-turning using the finite element method (FEM) is created in this paper to analyzed the formation mechanism and influencing factors of feed-direction burr in micro-turning. According to the simulation and analysis result, in micro-turning,the deformation of the workpiece feed direction end is the combined action of the plastic bending deformation and shear slip deformation, and plastic bending deformation influences burr height and shear slip deformation affects the burr root thickness. Meanwhile, due to the amount of material involved in different deformation actions is changed, compared with conventional scale cutting, the various influencing factors have significant differences effect on the size of burr.

Abstract: This article is for the integrity of the cutting surface, explaining the reason for the cutting residual stress generated from the mechanism, proposed several typical methods to reduce the residual stress. According to some experimental researches on cutting parameters which have been done by previous scholars, this article gives some analysis of the effects of cutting parameters of residual stress. And preliminary summary of the influence of residual stress on cutting parameters, it also provides a way for further discussion of cutting parameters and material effect on the machined surface residual stress distribution law.

Abstract: The importance of the surface integrity in modern machining is represented. Based on the notion of the surface integrity that was put forward by Michael Field, a new method of surface integrity characterization is presented in this paper. This method consists of surface quality, surficial coat quality and the edge quality. Then an evaluation system of surface integrity based metrology is constructed and has been applied in a machining process of nickel-base alloy turbine disk. The manufacturing time decreased by approximately 10%. In all, this characterization and the evaluation system of surface integrity are rational and efficient. This work let us be capable of breaking through in the systematical evaluation of present machining surface.

Abstract: The burr formation and control is one key technology of achieving precision and ultra-precision machining and automatic machining. Based on the theory of system engineering, the metal cutting burr formation, control and removal technology system are constructed in the paper. Then, the basic principles of burr control are presented. Combined with precision and ultra-precision machining and automatic machining, the active control methods and technologies of burr are presented. They are the modified design of parts structure, the option of tool geometry parameters, the adjustment of cutting data and processing technologies optimization etc. So, these methods lay a solid foundation on achieving minimum burrs.