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三维表面微观形貌的表征趋势 总被引:7,自引:0,他引:7
近几年计算能力,计算速度、图像分析、数据处理技术的不断提高,极大地推进了三维表面微观形貌测量仪的实用化和商品化。对最近文献中出现的三维分析方法和表征参数,如基准表面、图形(像)表征、等进行了综述,提出了三维表征技术的任务和发展方向。 相似文献
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目前对于微观粗糙表面模型的构建主要采用统计数学方法和分形方法,建模的前提基于大量假设和简化,不能真实反映表面形貌特征。因此提出了采用三维数字化测量与逆向工程相结合建立零件真实粗糙表面的方法,并分析微观接触性能。利用三维形貌测量仪测量得到真实粗糙表面形貌数据,并经过数据精简、去噪处理,采用逆向建模方法得到真实粗糙表面的三维实体模型;应用有限元分析技术,分析粗糙表面接触性能,包括结合面接触应力随载荷变化规律、不同加工方式零件界面真实接触面积变化规律,以及结合面受力-变形关系等。该方法有利于揭示零件微观界面接触机理,为进一步研究宏微观接触性能提供了方法参考。 相似文献
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超声磨削加工在难加工材料领域得到广泛应用,超声辅助磨削过程中,超声振动参数对磨削后的表面微观形貌具有重要影响,因此,为了在加工前对超声加工后的表面微观形貌进行预测,以优化加工参数。提出一种考虑耕犁的超声磨削表面微观形貌建模与预测方法。假设磨粒为球形,磨粒直径与间距服从高斯分布,给出砂轮形貌的数值生成方法;根据超声磨削运动学,建立考虑磨粒实时切削深度与耕犁影响的三维运动轨迹方程;在此基础上,提出超声磨削表面微观形貌生成的区域逼近求解算法,进而给出超声磨削表面微观形貌生成模型,模拟出超声磨削的三维表面微观形貌。通过试验分别从表面微观形貌的轨迹纹理、表面粗糙度数值两个方面对超声磨削表面微观形貌的模型的正确性进行了验证。 相似文献
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分形理论及其在机械结合面中的应用 总被引:1,自引:0,他引:1
简述了分形理论的产生经过,具体介绍了分形理论的几何概念.在指出机械加工表面具有统计自相似的结构的同时,介绍了用分形理论描述机械结合面微观形貌的优越性,进一步描述了近年来分形理论在机械加工表面的微观形貌特征的定量化描述中的应用现状.对传统描述方法和分形理论描述的精度及简易程度进行比较,结果表明运用分形理论来描述机械结合面的表面微观形貌特征有其独特的优越性,可以避免传统描述方法的多参数性,同时也解除了采样长度与仪器分辨率的影响.介绍了国内外的研究结果中分形理论在接触模型中的运用状况.认为分形理论最终会从二维发展到三维,能更精确地描述微观形貌,从而进一步建立精确的接触模型. 相似文献
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采用激光测量仪对车削机加工零件表面进行测量,获得零件亚纳米级的微观形貌数据,利用小波分析分时分频精细表达以及多分辨率分析的特点,建立粗糙表面多尺度重构模型,对基于真实测量数据的微观表面进行宏微观重构,并提出在不同尺度上提取粗糙表面的微凸体以精简数据的方法,从而实现在MATLAB和Pro/E中的微观表面建模仿真。提取的低频成分为零件表面二维和三维评定提供了基准,不同尺度上微观粗糙表面的重构为在不同精密等级上分析机加工工艺对零件表面粗糙度的影响提供了方法,Pro/E中重构的表面为有限元分析零件宏微观几何形貌与摩擦、润滑和密封的关联机制提供了几何模型。 相似文献
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通过原子力显微镜(AFM)实测得到机械结合面的真实三维微观表面形貌,同时基于分形理论模拟仿真得到了机械结合面三维微观表面形貌,分析结果表明,分形模拟表面形貌能较好地模拟机械结合面的真实微观表面形貌。进一步分别以实测的结合面表面形貌和基于分形理论模拟的表面微观形貌建立结合面的三维表面微观接触模型,运用有限元法进行接触仿真分析,研究真实微观表面之间的微观弹性及弹塑性接触特性,通过仿真分析得到Z向位移、接触面积和接触压力与接触载荷间的关系曲线。结果表明,基于分形理论建立的机械结合面分形模拟微观接触模型可以替代实测真实微观接触模型进行仿真分析。本研究能为深入开展结合面微观作用机理的研究提供理论依据。 相似文献
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激光检测摩擦力显微镜的定量标定 总被引:1,自引:0,他引:1
本文简要描述了激光检测摩擦力显微镜的工作原理,探索出一种横向力标定的有效方法,可以从横向力信号中提取摩擦力信号,从而能够定量地对试样表面的形貌和力学性质进行纳米量级的评定,以获取微观表面真实的三维形貌图和微观摩擦系数等信息,为纳米摩擦学设计提供依据。实验结果表明,用该方法测得未清洗单晶硅表面的微观摩擦系数约为0.06,和Bhushan等人的结果吻合的很好。 相似文献
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一种新型滚动轴承表面形貌测量仪 总被引:1,自引:0,他引:1
介绍了一种新型的滚动轴承表面形貌测量仪,它采用一种全新的能越过陡峭表面的二维位移传感器和垂直扫描三维工作台组成一个闭环控制系统,将传统的触针移动扫描方式改变为工作台移动扫描方式。在测量工件时,二维位移传感器的测量杠杆总是不断地回到平衡位置,因此即使增大量程,由杠杆转动所引起的测量非线性误差也非常小。该仪器不仅可进行二维轮廓测量,还可进行三维形貌测量,具有大量程、高精度、小测量力和更多测量参数等特点。 相似文献
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针对毫米级尺度线径和微米级尺度磨粒的金刚石线锯整周三维表面形貌测量难以实现与定量评价问题,提出一种基于轮廓法的圆周扫描表面磨粒形貌测量与分析方法。通过显微测量系统沿周向扫描采集金刚石线锯对应的边缘轮廓图像序列,经图像处理后获得金刚石线锯整个圆周表面形貌的坐标点云,采用三次样条插值法对数据进行平滑处理,经圆柱坐标变换处理,可重构金刚石线锯三维表面形貌。在金刚石线锯常用评价参数基础上,提出基于扫描过程二维投影轮廓和三维重构形貌的综合评价参数。采用自行研制的测量系统,对两个规格的线锯(线径外径分别为0.250 mm、0.320 mm;磨粒粒径范围30~40 μm)进行测量和评价。试验结果表明:该方法无需多次拼接,就可完成金刚石线锯整周三维微观形貌测量,并能实现对线锯特征参数的全面评价,可为线锯本身制造及使用过程中的工艺优化提供更加客观的基础数据。 相似文献
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The use of two-dimensional (2D) and three-dimensional (3D) topography data in assessing the functional significance of manufactured surfaces has formed a useful tool to production and design engineers for many years. However, over recent years, the development of numerical contact analysis methods has allowed much more quantitative analysis of both 2D and 3D topography data to be performed. Some examples of how this has led to real improvements in the performance and life of common engineering components such as rolling element bearings and gears are presented to demonstrate the potential of such methods. At present numerical contact mechanics analysis is simply a research tool, but programs are now reaching a level of sophistication and potential to be of general use as production and design tools. It is likely that, in the near future, they will form a further, and very useful, analysis option available on future surface metrology instrument data-analysis packages. 相似文献
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Optical shadowing offers a valuable technique for the study of many transmission electron microscope specimens. Simply blocking half of the illumination with the objective aperture produces an image with a striking shadowed effect which gives a distinctly three-dimensional appearance to the specimen's surface topography. Theoretical analysis shows that this is due primarily to a discrimination between electrons refracted in opposite directions, and that the characteristic features of the effect are successfully explained by a refraction model. The capability of visualizing surface topography is applicable up to the full resolving power of the instrument and accordingly opens many new avenues of investigation. 相似文献
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An analysis of the three-dimensional surface topography of textured cold-rolled steel sheets 总被引:1,自引:0,他引:1
The surface topography of cold-rolled steel sheet affects its press-forming behaviour and also influences the appearance of the end product after painting. In this study, the three-dimensional surface topography of several steel sheets processed by different technologies has been measured. Using statistical and signal processing techniques, two-dimensional power spectral density function, two-dimensional autocorrelation function and two three-dimensional characteristic parameters of the surface topography of each steel sheet are obtained separately. Through analyzing these parameters and charts of the functions, an investigation on three-dimensional surface topography of these steel sheets is performed. 相似文献
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Theoretical and experimental work on stylus flight is described. The paper describes the development of a simulation model for assessing the magnitude of surface topography distortion by stylus flight. Experiments on the surfaces support the theoretical model, which predicts stylus flight. The measurements of different surface topographies (including surfaces after grinding, turning, honing, milling) were done using Talyscan 150 measuring instrument with four traversing speeds (0.5, 1, 2 and 3 mm/s). The results of theoretical considerations and experiments were compared. The effect of stylus flight on surface topography parameters of measured surfaces basing on experimental investigation was assessed. The tendency was found that slope decreased, decrease of amplitude parameters and increase of horizontal parameters took place, but these effects were different for various surface types. The simulation procedure assured good accuracy of surface topography parameters changes.Based on theoretical investigation, the effect of stylus flight and stylus tip radius on parameters of computer-generated profiles was predicted. The choice of traversing speed to different types of surfaces was done. The parameters of biggest changes caused by error in measurement due to stylus kinematics were selected. 相似文献