PEEK不同表面粗糙度与分形维数关系研究

为探究PEEK不同表面粗糙度与分形维数之间的关系,在触针式表面轮廓仪上测量PEEK不同表面的粗糙度并采集了其轮廓曲线和数据。运用分形理论随机过程的结构函数方法,分析轮廓曲线的分形特征,并计算出不同表面粗糙度的分形维数。利用SPSS统计软件对粗糙度和分形维数关系进行拟合并得到最佳的拟合模型。结果表明:分维可以作为一个独立的表征参量来表征粗糙表面的复杂程度和粗糙度水平;PEEK的分形维数与粗糙度存在单调递减的关系,粗糙度数值越大,分形维数值越小;通过分形维数值与粗糙度之间的关系式,在一定范围内,可以通过粗糙度值计算得出分形维数值。     

多色光散斑表面粗糙度测量方法的研究

本文研究了具有均匀光强迭加的多色光象光斑测量表面粗糙度的方法。给出了多色光象光斑对比度C 与表面粗糙度参数Ra,Sm 的近似表达式。实现了对Ra,Sm 的非接触、快速测量。对磨削、端铣等试件的测量表明,在0.1μm≤Ra≤6.0μm 范围内,理论分析和实验结果是一致的,所测得的Ra 值与轮廓仪测量值相比较误差在15%左右。     

钢球表面粗糙度测量方法探讨

钢球表面粗糙度采用轮廓仪、干涉显微镜和激光粗糙度仪三种仪器测量，文章对三种测量方法中存在的问题进行探讨，并对现行钢球表面粗糙度评定方法的贯彻、轮廓仪测量时出现的问题如何处理，提出了看法。附表3个。     

PCD刀具几何参数对铝合金加工表面粗糙度的影响

文中研究了PCD刀具在不同的刀具几何参数下车削铝合金的加工表面粗糙度.分别改变刀具的前角、后角和刀尖圆弧半径3个几何参数做单因素切削试验,试验后利用表面轮廓仪测量工件的表面粗糙度,最后分析刀具几何参数对加工表面粗糙度的影响.     

表面微粗糙度椭偏法的测定

叙述了一种用椭偏技术快速测量表面微粗糙度的方法，推导了在单层膜模型下微粗糙表面的反射特性，给出了根据椭偏测量所得位相差△值估算均根粗糙度的公式以及对两种不同的微粗糙度表面测量的结果。     

表面微粗糙度椭偏法的测定

叙述了一种用椭偏技术快速测量表面微粗糙度的方法，推导了在单层膜模型下微粗糙表面的反射特性，给出了根据椭偏测量所得位相差△值估算均方根粗糙度的公式以及对两种不同微粗糙度表面测量的结果。     

表面粗糙度Rz值的测量与计算

微观不平度10点高度Rz是广泛应用的表面粗糙度基本评定参数之一。Rz比较直观,但只反映被测表面轮廓的峰谷起伏高度,不能表征不平峰谷的钝锐程度(几何特性)。测量时易受测量者主观影响,如选点不同,测量结果有较大差异。由于当前现有轮廓仪大多用于常用数值范围内(Ra为0.025～6.3μm,Rz为0.1～25μm)Ra值的测量,其余的,特别是超精加工表面粗糙度通常用光学仪器测量Rz,在此情况下对Rz值测量的研究更有必要。     

表面粗糙度测量仪工作台设计探讨

传统的触针式轮廓仪,由于易造成表面的损伤,以及只能在实验室环境下使用;而且测量时间较长,已不能满足需要。而一种非接触性的,测量快速、简便,甚至能实现在线或过程测量的表面粗糙度测试方法,则显得具有十分重要的意义。通过对现有触针式轮廓仪工作台的改进的研究,来实现对工作表面粗糙度的非接触式测量。它采用一种新型光纤传感器来测量表面粗糙度和微位移。基于光在粗糙表面的散射原理,采用散射光比法,能对Ra≤0.8um的粗糙表面实现快速、简便的非接触测量。改进后的轮廓仪与通用微型计算机相连,能满足在三维方向上测取粗糙度量值,并将其转化成数字量,用微机处理的要求。     

表面粗糙度轮廓仪快捷定位装置的设计改进

触针式表面粗糙度轮廓仪,是进行线粗糙度测量的专业精密量仪,具有超高精度的传感器。但因其传感器感应区间狭小,导致对复杂零件表面实施高精度的粗糙度测量时需反复安装调试,难以实现快速测量。通过反复实践摸索改进,设计制作了一套专用于表面粗糙度轮廓仪的辅助定位装置,通过测试验证与数据分析,有效证明该装置可大大提高微小复杂零件表面质量测量的工作效率。     

基体偏压对真空脉冲过滤弧沉积TiN涂层表面粗糙度的影响

采用离子束辅助真空脉冲过滤弧沉积技术,在硬质合金基体上制备了TiN涂层。对涂层的物理性能和机械性能进行了分析,利用XRD、SEM分别对不同基体偏压下沉积涂层的相组成和表面形貌进行了分析与观察,利用光学轮廓仪对涂层表面轮廓和表面粗糙度进行了测量,分析了基体偏压对TiN涂层表面粗糙度的影响。     

The factors affecting surface roughness measurements of the machined flat and spherical surface structures – The geometry and the precision of the surface

The quantitative determination of surface roughness is of vital importance in the field of precision engineering. This paper presents an experimental study of the roughness analyses for the flat and spherical surfaces of machined metal in order to compare the roughness data taken from the cloud data produced by the stylus type profilometer and two optical-based measurement instruments, namely the infinite focus microscope and the confocal laser scanning microscope.In this experimental study, the roughness measurements for fifteen flat and six spherical surfaces were repeated six times using three different measurement instruments. Great care was paid to measure the same location for each measurement. For the comparison of the measurement techniques, the same measurement process was applied to the flat and spherical surfaces individually, and the configurations of the measurement instruments (filter type, cut-off, resolution etc.) were synchronized. R_a, two-dimensional (2D) roughness parameter and S_a, three-dimensional (3D) roughness parameter were also compared. The measurement results for the samples having spherical surfaces indicated a considerably high difference in values taken from the stylus profilometer and two optical-based measurement instruments in contrast to those for flat surfaces.     

磨合阶段的机械密封端面形貌特征研究

表面粗糙度对机械密封性能有着显著影响。利用MMU-2摩擦磨损试验机和表面轮廓仪,对3个不同粗糙程度的密封端面进行了摩擦磨损试验。引入特征粗糙度,研究了3个不同粗糙程度的密封端面在摩擦磨损过程中的特征粗糙度变化规律,并与表面的轮廓算术平均偏差粗糙度变化规律进行了比较。研究表明,不同初始粗糙程度的端面在跑合过程结束后,粗糙度趋于一致。这一结果为利用特征粗糙度正确设计机械密封端面,合理选择端面加工方法提供了依据。     

磨合试验及磨合吸引子初探

为了表征磨合过程和磨合状态,掌握磨合过程中表面形貌的变化规律,在销-盘式试验机上对45#钢摩擦副进行了润滑条件下的磨合试验,用T1000型表面粗糙度测量仪和计算机数据采集系统测量磨合过程中的表面形貌和粗糙度值,并用分形方法对表面形貌进行分形表征和分形参数计算。研究表明:随着磨合过程的进行,摩擦副表面的粗糙度和分形参数逐渐变化,当达到磨合状态时,2个表面具有互适匹配的稳态参数值。因而从非线性科学原理出发,将磨合过程当作摩擦学系统的自组织过程,提出磨合吸引子的概念,并进行了初步的探讨。     

A study of the surface parameters of ground and lapped metal surfaces,using specular and diffuse reflection of laser light

Laser light, with a photocell giving a logarithmic response, is used to measure the specular and diffuse reflection from ground and ground and lapped metal surfaces. Theory suggests that the probability distribution of roughness heights determines the specular reflection, while the distribution of surface slopes determines the diffuse reflection. For specular reflection the theory gives useful results even in the range of grazing incidence (70° or 80°) which must be used for the roughness range 0.2 to 1.5 μm.The optical and profilometer results suggest skewed non-Gaussian probability distributions, and a theoretical model which may account for such distributions is suggested. The diffuse light results show that, except for the roughest specimens, the slope distribution is also non-Gaussian. The standard deviation of the slopes increases with roughness, and the relation between them is obtained.     

Influence of roughness parameters and surface texture on friction during sliding of pure lead over 080 M40 steel

In the present investigation, tests were conducted on a tribological couple made of cylindrical lead pin with spherical tip against 080 M40 steel plates of different textures with varying roughness under both dry and lubricated conditions using an inclined pin-on-plate sliding tester. Surface roughness parameters of the steel plates were measured using optical profilometer. The morphologies of the worn surfaces of the pins and the formation of transfer layer on the counter surfaces were observed using a scanning electron microscope. It was observed that the coefficient of friction and the formation of transfer layer depend primarily on the surface texture of hard surfaces. A newly formulated non-dimensional hybrid roughness parameter called ‘ξ’ (a product of number of peaks and maximum profile peak height) of the tool surface plays an important role in determining the frictional behaviour of the surfaces studied. The effect of surfaces texture on coefficient of friction was attributed to the variation of plowing component of friction, which in turn depends on the roughness parameter ‘ξ’.     

Surface damage during machining of solution treated and aged 18% nickel maraging steel I — Unlubricated conditions

The effect of cutting speed and tool wear land length on the surface damage produced during the machining of solution treated and aged 18% nickel maraging steel under dry unlubricated conditions was determined. Machined workpieces were examined with a scanning electron microscope and an optical microscope. Surface roughness was determined with a profilometer.The results of the investigation show that steady state machining can be carried out only over a very restricted range of experimental conditions where the surfaces generated show evidence only of fine scale surface damage. It is suggested that the fine scale surface damage is associated with the phenomena of continuous chip formation and of interaction between the tool nose region and freshly machined workpiece surface.     

Surface damage during machining of solution treated and aged 18% nickel maraging steel II — Lubricated conditions

The effect of cutting speed and tool wear land length on the surface damage produced during machining of solution treated and aged 18% nickel maraging steel under lubricated orthogonal conditions was determined. Machined test pieces were examined with a scanning electron microscope and an optical microscope. Surface roughness was determined with a profilometer.The results of the investigation show that steady state machining can be carried out only over a restricted range of experimental conditions, where the surfaces generated show evidence only of fine scale surface damage. It is suggested that the fine scale surface damage is associated with the phenomenon of continuous chip formation and interaction between the tool nose region and the freshly machined workpiece surface.Comparisons are made between the characteristics of surfaces machined under lubricated and unlubricated conditions and few differences are found.     

Two‐ and three‐dimensional profilometer assessments to determine titanium roughness

In this study, a comparative topography analysis of titanium (Ti) surfaces was performed using two‐ (2D) and three‐dimensional (3D) profilometers. Ti samples were either only sandblasted (SB) using Al₂O₃ particles or were SB and received an additional chemical treatment using a solution of 4% HF (SLA). Samples with no treatment were used as a control group (C). Therefore, three different surfaces were evaluated: SB, SLA and C. The Ti surface topographies were evaluated by scanning electron microscopy. An Ra roughness measurement was performed on each Ti sample by 2D and 3D profilometers. Surface roughness was also characterized using amplitude, spatial and hybrid 3D parameters. 2D and 3D profilometer analyses produced very close results. Mean Ra values range from 0.19 to 0.25 (C, p<0.05), 0.84 to 0.99 (SLA, p<0.05) and 0.98 to 1 µm (SB, p>0.05). The statistically different Ra values depending on the surface studied may be explained by methodological and technical differences. Also, 3D profilometer seems to be the more appropriate analytical method for measuring the roughness of Ti surfaces because it also describes surface organization. SCANNING 31: 174–179, 2009. © 2009 Wiley Periodicals, Inc.     

Surface damage during machining of annealed 18% nickel maraging steel Part 1 — Unlubricated conditions

The effect of cutting speed and tool wear land length on the surface damage produced during the machining of annealed 18% nickel maraging steel under dry orthogonal conditions was determined. Machined test pieces were examined with a scanning electron microscope and an optical microscope. Surface roughness was determined with a profilometer.The results of the investigation show that during machining a wide variety of different forms of surface damage is generated. The machined surfaces show extended regions where both coarse and fine scale surface damage have occurred at cutting speeds up to 0.1 m s^?1, whereas at cutting speeds greater than 0.1 m s^?1 the surfaces show evidence only of fine scale surface damage. It is suggested that the regions of coarse scale surface damage are associated with the phenomenon of partially discontinuous chip formation and the nucleation of cracks in the vicinity of the tool nose region. Several mechanisms of crack nucleation and propagation, which are thought to account for the occurrence of many aspects of the surface topography observed, are presented and discussed. It is suggested also that the regions of fine scale surface damage are associated with the phenomenon of continuous chip formation and interaction between the tool nose region and the freshly machined workpiece surface.It is shown that scanning electron microscopy is more indicative of the true condition of the surface than surface roughness measurements.