Papers by Author: Man Dong Zhang

Abstract: Using electroplating CBN hard gear-honing-tools with standard involute, the vicinity of the workpiece tooth pitch circle will be a “mid concave” error, the root of the tooth will be a “dig root” error generally. For the formation factors of the error are more complex, it is difficult to calculate errors with an exact analytical method. To this end, by using Pro/E and ANSYS software, the contact analysis of electroplating CBN hard honing process was simulated. The honed tooth surface normal deformation analysis was the important means to determine extent of tooth profile error, through the normal deformation analysis based on simulation results, the location and extent of normal deformation was determined. Practice shows that the location and extent of the normal deformation has been a certain relationship with processing gear tooth profile errors. It is provided a theoretical basis to make the gear-honing tooth surface modification as possible.

Abstract: In general, using electroplating CBN hard gear-honing-tools with standard involute, the vicinity of the workpiece tooth pitch circle will be a “mid concave” error, the root of the tooth will be a “dig root” error. For the form factors of the error are more complicated, it is difficult to calculate errors with an exact analytical method. To this end, by the help of Pro/E and ANSYS/LS-DYNA software, the analysis of electroplating CBN hard honing process was dynamically simulated. Through picking up the datum from analysis results, the von mises stress distribution curve was drafted along engaging points on the tooth surface, this revealed the internal factors of the tooth profile error formation, also determined the location and extent of the tooth profile errors. It is provided a theoretical basis to make the gear-honing-tool tooth surface modification as possible, and the result is consistent with the actual processing.

Abstract: After using plated CBN hard gear-honing-tools with standard involute tooth profiles, there will be the middle concave errors generally around pitch circle on the machined gear tooth surfaces. For the factors caused to errors are much complicated, it is difficult to calculate them accurately by the analytic method. Therefore, Using Pro/E and ANSYS software, the engaging situation between gear-honing-tool and gear was simulated and analyzed. Based on the results of the analysis, the abrupt changing extent of the compression stress was determined near pitch circle. Along the number of the machined gear teeth was changed, the abrupt changing extent of the compression stress was varied accordingly, which was also coincided with the middle concave errors. Those provided the theoretical foundation for the tooth profile modification of the hard gear-honing-tools, it was proved useful to reduce or eliminate middle concave error in practice.

Abstract: In the paper, polishing free-form surfaces of die are studied with magnetic abrasive finishing. The principle of magnetic abrasive finishing free-form surface, the design of magnetic pole, the composition and categories of magnetic abrasive are introduced. Through digitizing of free-form surface by using trimmed NURBS, based on residual roughness, machining accuracy and other parameters, the offset variable of free-form surface, which is the path of magnetic pole, is derived with the computer aided geometric design theory. These will provide theoretic foundation for the realization of finishing free-form surfaces of die automatically.

Abstract: Using plated CBN hard honing wheels with standard involute tooth profiles, there will be the middle concave error around pitch circle on the machined gear tooth surfaces. Therefore, standard involute tooth profiles of honing wheels have to be modified properly before electroplating CBN. In the paper, aiming at the tooth profile modification of honing wheels, the standard involute curve was converted into a spline curve, and control points of the spline curve were parameterized in solid modeling of honing wheels. By the Pro/E and ANSYS Workbench software, the engaging situation between honing wheel and gear was analyzed. Based on the analysis results, assuming the control points around pitch circle were set as variable parameter, and basically equal contact pressures were set as response variable parameter, the tooth surfaces of hard honing wheels were properly corrected, it was proved useful to reduce or eliminate middle concave error in practice.

Abstract: In the paper, a new technology combining conventional CBN electroplating and thermal diffusion in vacuum to produce gear-honing-tool for hardened tooth is introduced. The two factors, such as planting CBN abrasives and combination between electroplating layer and matrix that can affect the quality of gear-honing-tool, are investigated. Experiments show that using suspension CBN abrasive electroplating combined with thermal diffusion in vacuum can ensure the quality of planting CBN abrasives of gear-honing-tool and obtain the semi-metallurgy binding layer between CBN abrasives and matrix that withstands the force of honing gears.

Abstract: The theory and effect of gear-honing are wholly different between electroplated CBN hard honing wheel and epoxy resinoid soft honing wheel. In the paper, through deeply analyzing the mechanical character and engaging situation of both plated CBN hard honing wheel and gear, the bending deformation, contact distortion and cutting depth are calculated at engaging point. At last, the manufacturing technology combining conventional CBN electroplating and thermal diffusion in vacuum to produce gear-honing wheels for hardened tooth is introduced. These are important to improve the machining accuracy and finish of hardened gear tooth surface.