Materials Science Forum Vols. 471-472

Abstract: How to dispose and recycle the waste appliances properly and correctly is widely considered to be the focus in modern society. As to this case, in the paper, recycling methods, recycling processes, recycling apparatus and the integration of appliance recycling information have been studied according to different kinds of waste appliances, and finally an integrated appliances recycling management information system (ARMIS) is established based on the ideas studied. The system is an applied software, which is the integration of product information management, recycling process management and recycling product data management, and its purpose is to help recycling enterprises overcome the deficiency of information and management experience in the course of recycling, improve the recycling efficiency of the waste appliances and set a guideline for the operation and management of recycling enterprises.

Abstract: Because the machining of ultrasonic vibration assisted electro-discharge machining (UEDM) is a very complex process and it is too difficult to describe precisely every influencing factor with an accurate mathematics model, the study of parameters selection system is necessary and important for the practical application of machining method, the improvement of machining efficiency and minimizing the tool wear ratio (TWR). In this paper, the model and the corresponding database are built for UEDM based on the back propagation (BP) algorithm artificial neural network (ANN) to optimize machining parameters. Through learning and training, this system realizes the intelligent selection of machining parameters. As shown by the experiment results, the predictions accord with the test results, which shows that the reasonable and reliable project of UEDM can be provided by the system. With the increase of the machining sample, the machining database can be enriched and the application range will be expanded, so this system has the excellent fault-tolerance and extensible quality.

Abstract: An ingot aluminum alloy (Al-Cu-Mg-Ti-Sr) with high strength and high strain rate superplasticity has been successfully developed through a conventional manufacture route consisting of casting, heat treatment, hot extrusion with a low extrusion rate of only 10:1, hot-rolling and further cold-rolling, which is cost effective and suitable for large volume production industries. The tensile test result showed the alloy possesses not only a high ultimate strength of 513.85MPa at room temperature, but also a good high strain rate superplasticity with the tensile elongation of 174~224%, the flow stress of 17.1~33.9MPa and the strain rate sensitivity m-value of 0.174~0.293 in the initial strain rate of 3.16×10-2~1.0×10-1s-1 and at the temperature of 748K~793K. Differential scanning calorimeter (DSC) analysis showed that the superplastic deformation has no relationship with liquid phase. Scanning electron microscopy (SEM) analysis of fracture surface and surface showed that the superplastic deformation results from fine grain boundary sliding and dislocation slip.

Abstract: A reliable and sensitive technique of cutting tool condition monitoring in drilling is essential help for practising engineers. It is commonly known that a worn drill bit produces a poor quality hole. In extreme cases, a catastrophic failure of a drill bit during cutting can destroy a work-piece and damage a machine tool resulting in low productivity and expensive down time To detect the states of cutting tool wear condition, attempts are made to physically measure wear land. An intelligent system for detecting wear condition without interrupting the process is essential to avoid unexpected cutting tool breakage. In this work, an intelligent algorithm is proposed to real-time monitoring of drill wear states, in the form of a digital display, over a comprehensive range of cutting conditions. A novel neural network, Hybrid Neural Network (HNN), was developed and tested in this task. The results of the HNN have shown the ability to accurately monitor the wear states up to a 92% success rate. With such a highly accuracy of results, the developed system can be used for monitoring wear states in drilling and warning operators.

Abstract: Engineering geometric models are often designed to have symmetries and other regularities. In knowledge based reuse, creative design and design for mass customization, to have the information of such symmetries and other regularities from a geometric model is very useful. And this can make us understand more about the geometric model. In reverse engineering, B-rep models are created by fitting surfaces from point sets obtained by scanning an object using a 3D laser scanner. Each fitted surface is determined independently. The reverse engineered object can be improved by imposing these symmetries and other regularities on. This paper discusses the particular problem of finding partial approximate symmetries present in geometric model. A practical algorithm for finding partial approximate symmetries within a 3D B-rep model defined with planes, spheres, cylinders, cones and tori is presented. The experiment results show that the algorithm detects the symmetries expected and can do so reasonably.

Abstract: Kinematics, workspace, dynamics behavior of a 3-DOF 3-Legged parallel robot with horizontal slide 3-link for steel snagging, which was developed by Northeastern University, are introduced. The steel spot snagging experiments have also been carried out. The wheel selection, removal rate, grinding power and their influence factors are studied. Comparing with hanging grinders used in most steel mills of our country, this robotic grinder can reduce labor intensity of workers, raise efficiency and guarantee quality greatly.

Abstract: Nano technology is a new technology and begun in 1980’s. The paper firstly overviews the development of cermet cutter and its general situation in research, and then introduces the inherent properties owned by nano-technology and nano-material. In the end the nano-TiN modified TiC-based cermet cutter is fabricated and the mechanical properties of the developed cutter are also tested and analyzed. In order to study nano-modification effect, both nano-modified cermet and general cermet have been made. The mechanical properties of two kinds of materials are also measured. By comparing the measured datum, it has been indicated that the nano-modified cermet has better mechanical properties and the nano-modification technology is effective. This presents a new way to increase the toughness of cermet cutter.

Abstract: This paper provides a preprocessing flow for color three-dimension (3D) point cloud according to the characteristics of laser scanning data. The preprocessing methods and their functions are introduced in detail. Automatic system decision and manual polygon selection methods are applied to eliminate unwanted and noise data successfully, which possibly make improper color models reconstructed. A data reduction method is presented based on Grid reduction method considering color-boundary preservation. It can effectively avoid shape and color distortion in model reconstruction. Several experimental results are presented to indicate the feasibility and reliability of these methods, which can be broadly applied in various fields of products design, antiques and art wares digitization, etc.

Abstract: Nowadays more and more aesthetic product developments, assemblage and decoration designs are taking aesthetically appealing forms of natural objects such as rough terrain, ripples on lakes, coastline and seafloor topography. They are mathematical definable via fractal geometry theory and emerge to attract a lot of attention. However, not many methods for manufacturing of fractal objects have been reported in the literature and no previous research papers concern the manufacturability of fractal geometry. The paper will, thus, give a tentative classification and nomenclature of fractal geometry. Then, a state-of-the-art overview of manufacturing techniques is presented. By bridging the gap between fractal geometry and manufacturing, those processes that are promising to manufacture the three dimensional (3D) fractal objects will be highlighted. Afterward, a brief overview of limitation of those processes will be discussed.

Abstract: In this paper, a concept of extended Master Model is presented, mould features are classified and the master model of information hierarchy of mould is built. According to feature mapping theory, mapping categories of mould features are defined, mapping from mould features in various stage to cost feature field is implemented, which lays foundation for building cost information model of mould and implementation of cost oriented mould design.