Papers by Author: Gui Cheng Wang

Abstract: Green high-speed cutting is one of the main development directions of advanced processing technology.The defects of the traditional cooling and lubrication conditions and the deficiencies of external MQL (Minimum Quantity Lubrication) were analyzed in this paper. A new way of cooling and lubrication named internal MQL was highlighted, and an internal MQL system applied to turning was researched and designed. By high-speed turning of bearing steel GCr15 under different cooling lubrication conditions as dry turning, external and internal MQL, the comparative study of cutting force and surface roughness was carried out systematically. The results showed that the internal MQL has a comparative advantage, showing a good application prospect.

Abstract: The formation of burr is a common phenomenon in metal cutting, its formation and variation directly affects processing quality and production efficiency of the workpiece. It is one of the key technologies which were applied in precision or super-precision manufacture and automatic processing. Burr expert system is not only a communication platform between burr formation mechanism and burr removal technology, but also an important channel that promote the development of burr-free cutting technology. It was highly concerned by mechanical engineering experts and scholars at home and abroad. This study develops neural network (NN) metal cutting burr expert system with network function, facing the application of burr removal technology, making use of neural network technology and expert knowledge system technology, and closely integrating experimental study of metal-cutting burr. Combined with milling, the study on prediction burr sizes using the system is carried out. The results show that the predicted results and the experimental results are in good agreement, which demonstrates the system is feasible and effective.

Abstract: In the process of micro-cutting for the precision small parts, one of the main problems is the micro burrs. The finite element software Abaqus was used to simulate the micro-cutting process of aluminum 2024-T3. To create this model, Johnson-Cook (J-C) model was used to establish the material model, and Arbitrary Lagrangian Eulerian (ALE) method was used to separate the chip from work-piece. The contact friction models which was used between chip and tool was the modified Coulomb friction law. The formation process of micro burrs was simulated dynamically, and the effect of different cutting parameters and tool geometry parameters on burrs forming was analyzed. Furthermore, the general law was obtained. The results provide the guidance for optimizing the tool geometry parameters and cutting parameters to reduce the burrs in micro-cutting with the high surface quality.

Abstract: .The research which aimed at low integration and inefficiency of the management in the existing tool management of the machinery manufacturing enterprise (group) in our country, based on the tool whole life cycle theory to develop a tool whole life cycle management system. Tool whole life cycle management not only achieves tool operation management but also achieves tool cost management. The system could use network database to store the data and output the data by the form of sheet. And it achieved tool information inquiry, distribution and integrated management.

Abstract: Cutting direction burr/fracture is one of the important factors that influence the edge quality and performance of precision parts. A finite element model based on material failure mode is developed in this study to simulate the burr /fracture forming process. According to workpiece materials deformation and mechanical properties from the simulation results, the cutting direction burr/fracture formation process is analyzed. The cutting direction burr forms when there is a crack in the area near the tool tip and grow along the principal shear zone, the cutting direction fracture forms as the crack grow along negative zone.

Abstract: A new finite element model of BIG-PLUS tooling system are made, the BIG-PLUS tool holder and spindle deformation owing to centrifugal force generated by displacement, as well as different speed and clamping force of the radial displacement are analyzed and simulated. The results show that the radial clearance and deformation between spindle and tool holder can expand as the rotating speed increases, enhancing the clamping force and the shank of the spindle positioning accuracy and reliability of connection.

Abstract: Screw thread connection is a common way of detachable connection. The invalidation of screw thread connection will lead to mechanical failure or even retirement. Vibration tapping is essentially a kind of high-energy impact cutting which increases the rigidity of the tool. Composite vibration tapping simultaneously with repeated cutting action reduces the surface recovery of plastic materials and enhances metal cutting rate. Theoretical study and experimental results show that vibration tapping improves the metal cutting rates, enhances the machining accuracy and makes screw thread connection assembly easier. At the same time, vibration tapping process does not reduce the strength of screw thread. As the screw thread can be more uniformed cut at different depths, vibration tapping enhances the strength of screw thread slightly.

Abstract: The research which aimed at low integration and inefficiency of the management in the existing tool management of the machinery manufacturing enterprise (group) in our country, developed tool whole life cycle management system software. It based on the tool whole life cycle theory and adopted Microsoft Visual Basic 6.0 language and Access2003 database. The system could do a series of operation, such as, tool purchasing application, tool adding, tool modifying, tool inquiry, tool borrowing and return, tool breakage forecast. And it could make assembling and disassembling tool sheets according to techniques plan. The system could use network database to store the data and output the data by the form of sheet. And it achieved tool information inquiry, distribution and integrated management.

Abstract: The Cemented carbide cutting tool is widely used in more machining factory, the 5 types of cemented carbide materials: YT30+Ta, YTS25, YH1, 726 and 758 and Selected to make brazing and cutting test. The experiment results shown that: (a) the hardness of cemented carbide cutting tool after being brazed does not change, redoes HRA0.1~0.2; (b) YT30+Ta, YTS25 types of cemented carbide could be brazed using 105# solder, brazing quality could be very well; (c) Wear characteristic of machine-clamping and brazed cemented carbide cutting tool is normal and hardly change in T<150 minutes. The study makes theory and experiment foundation to widely use cemented carbide cutting tools.

Abstract: In this paper, the forming processes, main effect factors and change law of the cutting direction burr in orthogonal cutting have been studied and related theories are analyzed based on the cutting experiments. The result shows that the forming processes of cutting direction burr consist of normal cutting, flexure deformation of end surface of workpiece, plastic effect, continuous cutting and shear-break separating in orthogonal cutting. And a new phenomenon was found that cutting direction burr is formed with the shear-break separation of the chip and workpiece machined surfaces. In addition, the size of cutting-direction burr varies with workpiece materials, cutting parameters and geometric parameters of cutting tool. The study may be important science and practical value in order to control and reduce cutting burr in precision machining.