Papers by Author: Dun Wen Zuo

Abstract: : The effect of different surface topography on stress distribution of vacuum plate glass for the aluminum alloy braced pillars was analyzed by electrometric method. The results show that the maximum stress exists at the interfaces of all experimental glasses sheet and the top and bottom sides of a brace. The conclusion that the size of contact area between braced pillar and glass has an impact on stress distribution of the glass is obtained. The stress-strain field of different vacuum plate glasses was analyzed by the finite element method. The stress distribution of their important sides was obtained such as sealing side, supporting side and braced pillar. The experimental results are shown that high precision of the brace height and good flatness of the glass sheet considerably improve vacuum plate glass quality，such as its strength，its dependability and service life.

Abstract: . In this paper, the model of fixed abrasive diamond wire saw has been set up, and its cutting mechanism has been discussed. Then, the material removal rate model and wire saw cutting efficiency model have been established. the speed of wire saw, the number of the dynamic effective abrasive and the workpiece feed rate have been analyzed to study their impaction on the stability of cutting process. Finally, some rules and suggestions were brought forward.

Abstract: Chemical vapor deposition (CVD) diamond coatings were deposited on milling cutter substrate using a hollow substrate holder. The substrate is WC–Co cemented carbide contained 6% of cobalt concentration. Structures and stress state of diamond films were analyzed by scanning electron microscopy (SEM) and Raman spectroscopy. It was found that the diamond coating is of the same quality at the same cutting tool deposited on a hollow substrate holder. Diamond (sp3) bonds are better developed with substrate temperature of ~760°C. A higher or lower substrate temperature could lead to a higher non-diamond carbon content in the films. A higher substrate temperature could lead to a higher thermal stress. The compressive stress increases when the substrate temperature is higher or lower than 760°C. The concentration of amorphous phase in the coatings is low with CH4 concentration of 1.0% and 1.5%. A higher non-diamond carbon content and defects in the diamond coatings increase with the increase of CH4 concentration, which leads to the compressive stress value does not increase significantly under a high CH4 concentration.

Abstract: The compound of micron powders and nanometer powders is a magnificent step in the application and development of metal matrix composite reinforced by nanometer particles. By taking nano-Al2O3 powders and Ni-based micron powders as the research object, the preparation process of metal matrix micro/nano-powders reinforced by nanometer particles with high energy ball-milling is discussed from three aspects: the additive process of nanometer powders, the additive content of nanometer powders, and the required ball-milling time in the paper. The results show that the additive process of nanometer powders which uses directly the dispersed uniformly nanometer suspensions as grinding medium can effectively decrease and avoid nanometer powders’ agglomeration of composite powders. Nanometer particles are well distributed in the composite powders. The optimum additive content of nanometer powders is consistent with the theoretical model of mixture ratio, which is determined by the ratio of the average diameter of micron powders and nanometer powders and their density of corresponding solid materials. Meanwhile, the required ball-milling time for preparation of better uniformity composite powders is no more than 0.5hr. This implies that the preparation process has a high productivity. Moreover, the preparation process is verified through other nanometer powders including nano-SiC powders and nano-CeO2 powders.

Abstract: Design reuse is the application of past designs knowledge and successful experience to current design process and it is a significant method for rapid design. A knowledge-reuse-based rapid product design model is proposed and a three-factor product design iterative process model is studied. Finally, it is applied successfully in the rapid product design of construction machinery combining with the requirement of the construct machinery product design.

Abstract: The development history and situation of Chinese manufacturing enterprise informationization are reviewed in this paper. Based on practice, the problems of Chinese enterprise informationization are discussed on in view of understanding, methods and implementation, and difficulties are explained. At last, methods of Enterprise Information are proposed.

Abstract: In modern surface modification manufacturing technology, laser cladding is a high-tech which has good prospects for development. However, for the large area laser cladding surface modification, there has the contradiction between cladding efficiency and cladding accuracy of the cladding. If using the smaller spot, it will be inefficient, if the spot increasing, the accuracy of marginal part of the cladding will be poor, the "stage effect" will be obvious. The variable spot powder feeder is designed, and the variable spot cladding process with small facula outlining border and big facula filling in central section is introduced, which resolves the contradiction between the two effectively. Experimental proves that surface quality with variable spot cladding is better. In the overlap area, due to the second lixiviation caused by repeated heating, the microhardness value of multi-track overlap cladding is higher than the structure in the non-overlap area.

Abstract: The friction behavior of single silicon wafer sliding against different ice counterparts (α-Al2O3, CeO2 and SiO2) at 10±0.5 °C within a velocity of 60 rpm~300 rpm were studied using a home-made friction and wear testing machine. The morphologies and surfaces roughness of the worn silicon wafers were observed and examined on a non-contact surface topography instrument (ADE). It was found that the friction coefficient of the single silicon wafer decreased with the increase of sliding velocity. Single crystal silicon wafer coupled with α-Al2O3 ice counterpart recorded the highest friction coefficient and the biggest surface roughness, while it had the lowest friction coefficient and the smallest surface roughness as with CeO2 ice counterpart. One reason was that a series of tribochemical reactions occurred at the local contact point between the ice counterpart and the silicon wafer during sliding. Under alkaline condition, there would be a soft corrosion layer formed on the surface of the silicon wafer. Another reason was that the hardness of the abrasive particles was different and this caused different cutting depth of them.

Abstract: Diamond film was deposited on spherical molybdenum substrate by DC arc plasma CVD method. Diamond film morphology, purities and orientation evolution, obtained from atomic force microscopy, scanning electron microscopy, Raman spectroscopy, X ray diffraction respectively, has showed that grains on the growth surface are compact, continuous and uniform. Characteristic diamond (111), (220), (311) peaks were found and (111) facets were predominant. It revealed that diamond film was polycrystalline texture characteristic. There is a typical diamond Raman spectrum peaks at 1332.0 cm-1, and not graphite and amorphous carbon characteristic peak. High purity diamond film was deposited. When methane concentration was increased, diamond film has more local clusters and vacancy defects such as voids, graphite inclusion, and hydrogen cluster. Therefore, some important parameters such as methane concentration and substrate temperature should be optimized in depositing diamond film.

Abstract: Because of the fierce competition among manufacturers and customers’ diverse needs, it is essential for manufacturers to organize virtual organization to enhance their agilities to the market. However, the job-shop scheduling becomes very complex and very difficult in a temporary virtual organization. To achieve a harmonious collaborative engineering environment, a framework of agent-based collaborative job-shop scheduling is proposed and resource conflicts are discussed, and the theory of rough set and fuzzy appraise are applied to mediate these conflicts.