Papers by Author: Tian Biao Yu

Abstract: To investigate the effect of Li₂O, K₂O and ZnO on SiO₂-Al₂O₃-B₂O₃-Na₂O vitrified bond for CBN grinding wheels, the refractoriness and fluidity of specimens with different additions were studied. The bending strength was measured by three-point bending tester and the microstructures were observed by super Depth-of-Field microscope. The results show that Li₂O, K₂O and ZnO can reduce the refractoriness and increase the high-temperature fluidity. Li₂O and K₂O make a contribution to improving the bending strength; however ZnO is harmful to specimens’ mechanical property. Additionally, the fluidity is important to control the number of gas bubbles in specimen according to the microstructure analysis.

Abstract: In order to study the influence of grinding surface quality affected by grinding speed for CBN grinding wheel, the method of simulation and experimentation used to study grinding surface quality of CBN grinding wheel. First, on the basis of grinding wheel topography, the influence of grinding surface quality affected by grinding speed was analyzed by adopting motion simulation method. Then, high-speed grinding experiment was carried out to three kinds of metal materials, and machined surface roughness and surface hardness after processing are measured and researched. Test shows that “speed effect” is remarkable in grinding metal materials. As the grinding speed increases, the grinding surface quality of workpiece is gradually improved. With the speed increasing, surface roughness of workpiecedecreases, and at lower speeds the surface roughness dropped more obvious. With grinding speed increases further, the change of roughness tends to be slow, and the bending point appears at about 100m/s.Surface hardening degree decreases with grinding speed increasing, when grinding speed up to high-speed grinding stage, the degree of hardening of the workpiece is more soothing.

Abstract: Flexible manufacturing cell (FMC) was the extension of the CNC machining center,which consisted of three portions , a CNC machining center , an industrial robot and unified by a the background computer programmable control. In order to guarantee the rationality and feasibility of the automatic operation loading and unloading workpieces , the simulation object was based on the KUKA robot of flexible manufacturing cell in this paper, which based on MATLAB/GUI and combinated of VRML language and information transmission method development between MATLAB and the simulation system of flexible manufacturing unit. According to the set up parameters and angles, the model was implemented. Through the control panel and the robot's real-time interactive simulation, 3d visualization window can be real-time display of the robot simulation, and validated the path planning. According to the simulation results of the model , it could provide reference to the actual movement of the KUKA robot trajectory planning, provided the better fully automated feasibility analysis of flexible manufacturing cell, and proved the improvement of flexible manufacturing unit operation scientifically and reasonably.

Abstract: For ultra-high-speed grinding, the deformation of grinding wheel has a greater impact on the machining accuracy. Finite element method was used to study the radial deformation of the CBN grinding wheel considering centrifugal force and grinding heat. The study shows that the effects of centrifugal force and grinding heat are same magnitude, and the proportion changes with the change of grinding speed and grinding force. By finite element analysis, it is possible to solve the grinding wheel the radial deformation and grinding temperature under different grinding speed and grinding force, and it also provides theoretical support for predicting the machining accuracy, compensating precision and avoiding grinding burn.

Abstract: Building 3D model for a new type direct-drive NC Turret tool post, and introduce the model into ADAMS for further kinematics and dynamics simulation. In the kinematics simulation, observing the motion process of the direct-drive NC turret tool post and plots the trajectory of moving parts to a curve. Simulate the force condition of the NC turret tool post in actual situation, calculate the axial load and verify the clamping force in dynamics simulation.

Abstract: As an organizational way, virtual enterprise had been the development tendency of contemporary enterprise operation. For complex market opportunities, the uncertainty of supply chain in virtual enterprises was the key of enterprise operation. This paper studied the production and order strategy for virtual enterprise members from single-stage supply chain, and then provided reference for subsequent multi-stage supply chain. This paper introduced expected loss, which was the base of making decisions for the enterprise. Through building the mathematical based on the strict mathematical derivation, the quantitative relation between the order quantity of core enterprises and production capacity of partners, and then the mathematical model was verified in the last.

Abstract: Grinding is often used as the final manufacturing method which is an important processing method. Its’ quality of parts surface will directly affect the life and strength of mechanical parts. Therefore, the quality of parts surface in grinding is particularly important to mechanical parts. In this paper, after the simplification of theoretical model of the parts, we can use software such as WORKBENCH and MATLAB to obtain the temperature field of grinding and numerical simulation in case of 45# steel. Subsequently, it also makes use of LS-DYNA to carry out micro-morphology’s simulation in the process of grinding. Then it can significantly verify the previous simulation’s results. We preliminarily obtain the mechanism of the grinding burn on parts surface. It also shows the concrete impact on temperature field with the changing of grinding parameters. Finally we can receive the method to minimize the grinding burn.

Abstract: The carrying of Liquid hybrid bearing for ultra-high speed grinding is complex. The oil film temperature distribution in different input state is obtained through CFD analysis by FLUENT. On this basis, the temperature characteristics laws of the oil film with the input parameters change were obtained. Analysis shows that the relationships of oil film temperature with spindle speed and eccentricity are directly proportional and super linear, the relationship of oil film temperature with oil supply pressure is inverse ratio and the relationship with oil supply temperature is approximation directly proportional to the linear. Finally the significant of the various input parameters are analyzed through the orthogonal test. The results show that the effect of spindle speed is most significantly.

Abstract: Two-phase flow diaphragm pump (hereafter referred to as the diaphragm pump) is a new generation pump of the reciprocating pump, which used to transport high fretting corrosion medium. At present, the diaphragm pump is widely used in many fields such as Non-ferrous metals, Chemical, Coal, Electric power and so on. The diaphragm pump is of the heart of the equipment; therefore it must have the very high reliability. As the important part of diaphragm pump, the dynamic characteristics of the power end will directly affect the behaviors and life of the solid machine. This paper introduces the work principle of the diaphragm pump, carries a simulation to the virtual prototype of the diaphragm pump based on the numerical value analyze software MATLAB and the dynamics of mechanical system simulation software ADAMS and get the relationships between the design parameters and the dynamic characteristics of the power end of diaphragm pump, which provide a theoretical basis for optimizing the diaphragm pump in the future.

Abstract: Based on metal cutting theory and the key technology of finite element simulation, this paper uses finite element software Deform to establish three-dimensional finite element simulation model and simulate cutting process. This paper uses the work piece material is IN718 high temperature alloys packaged in Deform, and analyzes the processing characteristics of high temperature, choosing the right tools and cutting dosages to simulate. Through the simulation we can get scraps forming process, the surface stress, strain, temperature and cutting force distribution of the workpiece and the tool. We can also get the change rule of cutting force and cutting temperature under the different cutting parameters. The simulation results provide the theoretical basis for the optimization of cutting parameter selection in production practice.