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Different from other applications, this paper explores how to use the stable high-Tc superconducting (HTS) magnetic levitation (maglev) to lift the sculpture art to a high levitation position for satisfying the artists requirement for the light artistic concept. With a combination of the permanent magnet (PM) levitation and HTS maglev technologies, a sculpture model was built to sustain a stable levitation with a levitation height of over 80 mm. In this hybrid HTS maglev sculpture model, three PM rings are arranged as upper, middle, and bottom as a double-layer axial levitation structure; six rectangular YBaCuO bulks are fixed along the side of the PM rings upper-layer as a stabilizer component along the radial direction. When the bottom PM ring was driven up by the lifting bolt, the upper PM ring, which was fixed with the art, can be lifted much higher. Then the required artistic effect will be enhanced. After the model was designed and optimized by finite element method, it was experimentally validated by the HTS maglev measurement system. This levitation design is helpful to the realization of a real-scale levitation sculpture art, and can also provide references to superconducting radial magnetic bearing systems.

A mechanical model of surface roughness is established based on the Kragelskii-Drujanov theory of friction and wear and Hertz elastic contact theory. Effect of material flow stress on remnant height of the machined surface was investigated. Test showed that the machined surface morphology provides the phenomena of the side flow in the vertical direction of ploughing in high-speed machining. The remnant height values on the machined surface of the high-speed machining are obtained by DEFORM-3D simulation. Based on the results it can be concluded that the surface roughness values of the workpiece increase with material flow stress.

Gear honing with globoid honing worms is seldom used because it has no distinct advantages to honing with internal geared honing rings. The paper puts forward a new process to honing gear with globoid honing worms on hobbing machines. First the globoid honing worm is profiled by diamond dressing gears, which has the same geometric parameters with the machined gears. Then the profiled globoid honing worm is used to hone workpieces. Both the profiling process and honing process are implemented on same hobbing machines. Meshing and Tooth contact analysis of globoid honing worm profiling has been considered. Meshing equation of profiling process and equation of globoid honing worm tooth flank after profiling are obtained. Experiment testified that it is an applied process and has many advantages.

The gear honing process is a widely used process for gear finishing after heat-treated, and may be divided into the variants “internal-tooth honing” and “external-tooth honing”. External- tooth honing is seldom used in gear finishing due to lower overlapping ratio and relatively low precision. But its process cost is much lower than internal-tooth honing and gear grinding. The paper puts forward a new method to improve the precision of external-tooth honing, i.e. honing ring is profiled by diamond dressing gears, which have the profile of the workpiece to be machined. Meshing and Tooth contact analysis of honing ring profiling has been considered. Meshing equation of profiling process and equation of honing ring tooth flank after profiling are obtained. Experiment testified that it is an applied method and has many advantages.

The gear plunge shaving process is a widely used process for soft finishing of gears in the gear manufacturing industry. But it is difficult and expensive to profile plunge shaving cutter, because the cutter must be ground by a cone grinding wheel on a special grinder. A new method, profiling gear shaving cutter on the shaving machine, i.e. a CBN dressing gear which has the same parameters with the machined gear is clamped in place of the workpiece on the shaving machine and profiling the cutter in shaving process, is put forward. Meshing and Tooth contact analysis of shaving cutter profiling has been considered. Meshing equation of profiling process and equation of shaving cutter gear blank after profiling are obtained. Experiment testified that it is an applied method and has many advantages.

This paper focuses on developing an empirical model for the prediction of milling forces in high-speed end milling of P20 die-mold steel. The spindle speed, feed rate, axial and radial depth of cut are considered as the affecting factors. The data for establishing the model are derived from high-speed end milling experiments conducted on a 5 axis machining center according to the principles of DOE (design of experiments) method. The influences of milling parameters on milling forces are investigated by analyzing the experimental curves. Consequently, multiple-regression analysis is applied in developing the empirical model. Furthermore, the significances of the regression equation and regression coefficients are statistically tested in this paper to validate the model.

An orthogonal cutting model was presented to simulate high-speed machining (HSM) process based on metal cutting theory and finite element method (FEM). The residual stresses in the machined surface layer were obtained with various cutting speeds using finite element simulation. The variations of residual stresses in the cutting direction and beneath the workpiece surface were studied. It is shown that the thermal load produced at higher cutting speed is the primary factor affecting the residual stress in the machined surface layer.

This paper proposes a numerical cutting model with the FEM to simulate the temperature field at the contact zone on the tool rake face. The analysis of the tool rake face temperature in orthogonal machining is studied based on heat transfer theory and calculus of variation. Then, the FEM simulation results of the temperature field on the rake face in various cutting speeds and the cutting speeds vs peak temperature curves are given. The results show that the highest temperature of the tool surface is located at a distance nearby the tool tip, and the higher cutting speeds can increase the tool rake face temperature obviously. In addition, the workpiece materials have a great effect on the peak temperatures at the rake face. Therefore, this study is helpful to investigate tool wear mechanism and optimize the machining parameters for the metal cutting processes.