Application of the Taguchi Method to the Optimization of the Submerged Arc Welding Process

Application of the Taguchi method to the optimization of the submerged arc welding process is reported. The Taguchi method is used to formulate the experimental layout, to analyze the effect of each welding parameter on welding performance, and to predict the optimal setting for each welding parameter. Experimental results are provided to confirm the effectiveness of this approach.     

田口方法在冲压仿真建模参数优化中的应用研究

利用现有的有限元软件ABAQUS,建立了V形件冲压加工的有限元仿真模型。结合田口方法,通过实验数据和仿真结果对比,分析了各建模参数对仿真模型鲁棒性的影响,最终找出有利于提高鲁棒性的建模参数组合,建立了可运用于实际分析的鲁棒性有限元模型。给出了V形冲压件基于田口方法的有限元建模参数优化的计算实例。结果表明,所提方法是有效且实用的,为提高有限元建模的鲁棒性提供了依据。     

Development of Catalytic Converters Using Detonation Spraying

One of the trends in hydrogen power engineering is the development of devices for the preparation of synthesis gas by the catalytic reforming of a hydrocarbon feedstock. Studies show the advantages of catalytic converters based on a modular catalyst support with a honeycomb-type structure produced from a metal foil, both sides of which are coated with highly porous oxide ceramics. The drawback of this design is a poor ability of the coating to withstand high-temperature operating conditions. The coating may detach from the substrate because of the difference in thermal expansion coefficients between the metal foil and the ceramic coating. Besides, a corrosion of metal foil takes place. The result of the present study is the development and application of a two-step coating method, which allows significantly increasing the service life of the catalyst supports. At the first step, a low-porosity ceramic layer is deposited on a metal foil by detonation spraying. At the second step, a high-porosity layer of a ceramic catalyst is deposited from suspension. In this work, the peculiarities of the detonation spraying of the ceramic coating on a metal foil and the design of the obtained catalytic converter have been addressed.     

Optimization of Polishing Parameters with Taguchi Method for LBO Crystal in CMP

Chemical mechanical polishing(CMP)was used to polish Lithium triborate(LiB3O5 or LBO)crystal.Taguchi method was applied for optimization of the polishing parameters.Material removal rate(MRR)and surface roughness are considered as criteria for the optimization.The polishing pressure,the abrasive concentration and the table velocity are important parameters which influence MRR and surface roughness in CMP of LBO crystal.Experiment results indicate that for MRR the polishing pressure is the most significant p...     

单片机在测试炸药爆速中的应用

测试炸药爆速的时间精度要求０．１μｓ一批炸药要求测试５个样品，然后计算出它们的平均值和标准差，看是否达到标准要求，文中介绍了了单片机电路和相关的程序实现以上的测试和计算功能。     

Parametric Optimization of Centrifugal Force-Assisted Abrasive Flow Machining (CFAAFM) by the Taguchi Method

Extrusion honing, known as abrasive flow machining (AFM), deburrs, polishes, and radiuses surfaces and edges by flowing an abrasive-laden media over these areas. The process is particularly used on internal shapes that are difficult to process by other nonconventional machining processes. Because abrasive action occurs only in areas where the flow is restricted, tooling is used to direct the media to the appropriate areas. Like other nonconventional machining processes, AFM has the limitation of lower material removal rates. The application of centrifugal force (by using rotating rectangular rod inside the hollow workpiece) has been explored for the productivity enhancement of the process. This article reports that centrifugal force enhances the material removal rate (MRR) and improves the scatter of surface roughness (SSR) value in AFM. It outlines the development of a system that determines sets of viable process parameters for a new process called centrifugal force-assisted abrasive flow machining (CFAAFM). Cylindrical workpieces of brass are used for the experiment. During the experiments, parameters, such as rotational speed of rectangular rod, extrusion pressure, and grit size, were varied to explore their effect on material removal and scatter of surface roughness. Taguchi's parameter design strategy has been applied to investigate the effect of process parameters on the MRR and SSR values.     

Al2O3陶瓷爆炸喷涂涂层性能分析

使用爆炸喷涂法制备了Al2O3陶瓷涂层,以自熔性NiAl合金粉末作为底层,基体为45钢。涂层的XRD图谱分析表明,爆炸喷涂的Al2O3陶瓷涂层结构以α-Al2O3及γ-Al2O3为主,说明在爆炸喷涂中存在相变过程;使用国标JB/T7509-94铁试剂方法进行测定,Al2O3陶瓷涂层孔隙率为0.019个/mm2,爆炸喷涂的Al2O3陶瓷涂层结构致密;滑动磨损试验说明,爆炸喷涂Al2O3陶瓷涂层提高了钢基体的耐磨损性能,适用于耐磨涂层。     

Optimization of Plasma Arc Welding Parameters by Using the Taguchi Method with the Grey Relational Analysis

The optimal parameters process of plasma arc welding (PAW) by the Taguchi method with Grey relational analysis is studied. The Grey relational grade is used to find optimal PAW parameters with multiple response performance characteristics. The welding parameters (welding current, welding speed, plasma gas flow rate, and torch stand-off) are optimized with consideration of the multiple response performance characteristics (the penetration of root, the weld groove width, and the weld pool undercut). As a result, the improvement percentage of the Grey relational grade with the multiple performance characteristics is 31.8%. It is shown that the multiple response performance characteristics are greatly improved through this study.     

Application of Taguchi methods to surface mount processes

This paper describes the implementation of a Taguchi experiment for the placement of surface mount components as part of a process at Mars Electronics. The justification for the experimental work, the practical problems in its implementation and the significance of the results obtained are described. The experiment is seen as part of a programme and the implications of the results obtained for subsequent experimentation are discussed.     

Optimization of carbon fibre production using the Taguchi method

Since the variation of carbon fibre mechanical properties is very large, the Taguchi method was used to produce carbon fibre in a pilot plant, and to improve the properties of carbon fibre. Due to the production conditions of the Taguchi method, the tensile strength, modulus and breaking elongation of carbon fibre are increased by about 20, 13 and 26%, respectively.     

基于田口方法的小批量生产过程控制

针对传统过程控制方法在小批量生产领域面临的样本量不足而导致的统计特性减弱的困境,运用田口式反馈控制技术对某军品关键件生产过程建立起质量损失函数,计算出了最优过程控制方案,并绘制田口式反馈控制图进行监控.计算结果表明,过程控制成本有显著降低,过程能力显著提高.     

变尺度法在光学优化中的应用

详细介绍了一种优化算法－变尺度法并把这种算法借助Ｃ语言开发的程序用于光学优化设计中，设计了几种典型的光学系统。设计过程中表现了这种方法的快速收敛性和稳定性，结果和理论相符。     

无源光纤探针在爆轰实验中的应用

利用熔石英在冲击作用下发光的特性开发了一种测量冲击到达时间的无源光纤探针技术。当冲击波阵面到达光纤探针端面时会产生一个瞬时光信号,这个光信号经光纤传输到光电探测器,变换为电信号后由示波器记录,通过判读就可以知道冲击波阵面到达光纤探针的时刻。该探针无需外加信号源,响应时间可达亚纳秒,抗电磁干扰,可对非金属材料进行直接测量。目前,该探针在爆轰实验测试中得到了大量的应用,本文给出了利用光纤探针测量LY12样品中的冲击波速度、电炮加载的Mylar膜飞片的平面性以及GI-920炸药的爆轰波形的实验方法和结果。     

Optimization of Removal Rate and Weibull Modulus in Polishing of Ceramic Blocks Using the Fuzzy-Based Taguchi Method

This paper not only analyzed the Weibull modulus through reliability engineering but also obtained the optimal parameters with multiple performance characteristics using the fuzzy-based Taguchi method for polishing ceramic blocks. Optimization with the multiple performance characteristics is found to be the highest speed and greatest load, and diamond particle of 3 μm and 30% concentration. The analysis of variance shows that the most significant polishing parameters are load (57.75%) and speed (24.43%), followed by concentration (12.52%) and diamond particle size (5.30%). Experimental results have shown that the multiple performance characteristics can be improved effectively through this approach.     

Optimization of CVD growth of CNT-based hybrids using the Taguchi method

Taguchi method, extensively applied for the optimization of multifactor processes in the most diverse fields, is for the first time applied to the synthesis of hybrids based on C nanotubes by iron-catalyzed chemical vapor deposition in 1:1 i-C₄H₁₀ + H₂ atmosphere. For this purpose, assumed synthesis-temperature (500 °C, 600 °C or 700 °C), support-material (alumina, magnesia or Na⁺-exchanged K10 montmorillonite), calcination (450 °C, 600 °C or 750 °C) and reduction (500 °C, 600 °C or 700 °C) temperature of the iron catalysts as the four factors of importance in the process, nine suitably designed experiments are conducted and the influence is evaluated of the four three-level factors on the issue of the process in terms of selectivity toward nanotubes, catalytic yield and content of carbonaceous and metallic impurities in the C nanotubes. By this procedure, the configurations giving optimal results are predicted, and tested by carrying out new experiments.     

超音速火焰喷涂简化数学模型及其应用

应用燃料燃烧理论、气体动力学和两相流原理,建立了超音速火焰喷涂焰流特性和粒子加速、加热行为的简化模型,并在计算机上进行了数值求解.研究了气、油质量比(空气过剩系数)对燃烧室焰流温度及相关参数的影响.结果表明,随着气、油质量比的增大,燃烧室焰流温度明显降低,因此气、油质量比不宜过大.另外,预热助燃气体是提高燃烧室焰流温度的重要措施.燃烧室焰流压力越快,焰流出枪速度越大,但焰流出枪温度越低.喷涂WC-Co系合金时,合理的燃烧室焰流压力约为0.6MPa.粒子出枪后,粒子速度和温度均先增大后降低,因此存在一个合理的喷涂距离.针对所研究的条件,合理的喷涂距离约为0.1m.     

路由器产品生产流程改善

以一种路由器产品的生产流程为例,运用流程程序分析法对生产流程的整个生产过程进行分析、研究,以消除和改变整个生产过程中不合理的作业内容、作业方法以及作业现场的空间配置.通过对生产流程的分析、研究和改进,设计出科学高效的作业方法、作业程序,提出合理的空间配置方案,使得改善后的生产线能够适应多种成熟产品的大量生产,提高生产效率.