METHODOLOGY TO COMPARE 3-D AND 2-D PARAMETERS FOR THE OPTIMIZATION OF HARD TURNED SURFACES

Hard Turning provides an alternative to grinding in some finishing applications. Average Surface Roughness R_a has been widely used in industry to establish surface texture needed for a given application. It is known that the single parameter R_a is inadequate to define the functionality of a surface texture. The quality of a surface can be determined by the nature of its interaction with another surface. Thus a surface with significant peaks will not make as good a bearing surface as a surface with deep valleys and low peaks. Two different surfaces with similar values of R_a can behave differently under fatigue loading conditions. 3-D visualization of expected surface texture will facilitate optimization of machining parameters to produce function-specific surfaces. The advantages and shortcomings of some current surface texture prediction models are discussed. A new method based on neuro-fuzzy techniques is proposed. Optimization using some 3-D surface parameters was carried out and compared with the results of those obtained using 2-D parameters.     

汽车模具复杂棱脊和沟槽的数字化及激光加工轨迹规划

针对大型汽车冲压模具复杂棱脊和沟槽的数字化问题提出了三维自适应测量算法。为适应于激光表面强化加工的特殊要求,在后续测量数据处理过程中建立了复杂棱脊和沟槽的简化数学模型,提出了六维激光加工轨迹规划算法,并进行了测量和加工试验验证。上述算法都已应用到集成化柔性激光加工系统中。     

有分流叶片的径流式压气机叶轮考虑上下游影响的三元流场计算

对有分流叶片的径流式压气机叶轮作叶片面的上下游延伸流面,在接长了的叶轮叶片通道内,用准正交面法求解三元流场。本方法可应用于这类叶轮存在进口预旋情况下的流场分析,也可应用于变工况流场分析。