Chipping Detection in Ceramic Insert during Turning by Analysis of Workpiece Surface Profile Using Cross-Correlation

Accurate prediction of the material removal rate (MRR) distribution is very important for the control of the polishing process. However, the widely used prediction method of MRR based on the Preston equation is still incapable of predicting the roll-off phenomenon in polishing process. One of the reasons is that many of the researchers’ neglected the effect of the surface profile of the workpiece on the MRR. In this paper, the evolutionary process of MRR distribution with the change of surface profile using two different polishing pad is studied, it is found that MRR varies gradually with the change of surface profile and tends to be uniform finally. Based on the analysis of contact pressure considering the actual surface profile of workpiece and modified Preston equation, the distribution of MRR is analyzed. It is found that the Preston coefficient distribution on workpiece surface is stable when the surface profile variation is small and shows obvious differences from the center to the edge of the workpiece. Through the comparison it is found that correlation between the regularities of Preston coefficient distribution and the type of polishing pad is significant. The research results in this paper will play an important guiding role in the quantitative prediction method research of polishing process.

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Ultrasonic Cavitation Peening of Stainless Steel and Nickel Alloy

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4025756 ◽

2013 ◽

Vol 136 (1) ◽

Cited By ~ 12

Author(s):

Yibo Gao ◽

Benxin Wu ◽

Ze Liu ◽

Yun Zhou ◽

Ninggang Shen ◽

...

Keyword(s):

Surface Roughness ◽

Stainless Steel ◽

Nickel Alloy ◽

Vibration Amplitude ◽

Surface Hardness ◽

Surface Profile ◽

Ultrasonic Cavitation ◽

Surface Microhardness ◽

Workpiece Surface ◽

Different Depths

Ultrasonic cavitation peening is a peening process utilizing the high pressure induced by ultrasonic cavitation in liquids (typically water). In this paper, ultrasonic cavitation peening on stainless steel and nickel alloy has been studied. The workpiece surface microhardness, the microhardness variation at different depths, the workpiece surface profile, roughness, and morphology have been measured or observed. It has been found that for the studied situations, ultrasonic cavitation peening (at a sufficiently high horn vibration amplitude) can obviously enhance the workpiece surface hardness without significantly increasing the surface roughness. Under the investigated conditions, a surface layer of more than around 50 μm has been hardened under a horn vibration amplitude of ∼20 μm.

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Ultra-Precision Shaping and Polishing Experiments in Nanoparticle Colloid Jet Machining

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.291-294.1759 ◽

2011 ◽

Vol 291-294 ◽

pp. 1759-1763 ◽

Cited By ~ 1

Author(s):

Xiao Zong Song ◽

Yong Zhang ◽

Fei Hu Zhang

Keyword(s):

Atomic Force Microscopy ◽

Morphological Characteristics ◽

Surface Profile ◽

Surface Shape ◽

Workpiece Surface ◽

Force Microscopy ◽

Atomic Force ◽

Ultra Precision ◽

Nanoparticle Colloid ◽

Observation Results

In this paper, ultra-precision shaping and polishing experiments have been done to research the shaping and polishing characters of nanoparticle colloid jet machining. A high-purity quartz glass sample with aspheric surface profile was employed as workpiece and polished by nanoparticle colloid jet machining. We utilized surface profilometer to measure the surface profiles of workpiece before and after shaping by nanoparticle colloid jet machining. The measurement results indicate that the nanoparticle colloid jet machining has good shaping ability to satisfy the demands for surface shape correction in ultra-precision machining. Atomic force microscopy (AFM) was utilized to observe the surface microscopic morphological characteristics of the workpiece surface polished by nanoparticle colloid jet machining. The observation results show that the roughness of the workpiece surface has been reduced from 1.919 nm RMS to 0.784 nm RMS by nanoparticle colloid jet machining. Based on the atomic force microscopy observation results, power spectral density analyses have been done to evaluate the polishing performance of the nanoparticle colloid jet machining.

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Study on Surface Topography and Texture of Workpiece Machined by Tangential Turn-Milling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.569.144 ◽

2012 ◽

Vol 569 ◽

pp. 144-148 ◽

Cited By ~ 1

Author(s):

Shan Ren

Keyword(s):

Fractal Dimension ◽

Surface Texture ◽

Surface Profile ◽

Lower Surface ◽

Machined Surface ◽

Workpiece Surface ◽

Surface Fractal Dimension ◽

Rotating Speed ◽

Surface Fractal ◽

Turn Milling

By measure and calculate related parameters of Tangential Turn-milling machined surface profile, the fractal dimension of the surface was got when machined in different feeding and rotating speed . Results show that the fractal trait can express the information of workpiece profile surface texture ; With the increase of feeding, workpiece surface fractal dimension was reduced and the structure of surface texture was become thin; along the increase of ratio of revolution, workpiece surface fractal dimension was increased, the structure of surface texture was become compactness and have the lower surface texture height.

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Research on Diamond Wheel’s Specialties during ELID Ulterprecision Grinding of Silicon Nitride

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.51 ◽

2011 ◽

Vol 295-297 ◽

pp. 51-55

Author(s):

Wei Dong Jin

Keyword(s):

Silicon Nitride ◽

Surface Profile ◽

Grinding Wheel ◽

Cutting Depth ◽

Insulator Layer ◽

Silicon Nitride Ceramic ◽

Workpiece Surface ◽

Abrasive Grain ◽

Materials Research ◽

Hard And Brittle Materials

Taking ultraprecision grinding of silicon nitride ceramic as an example, this paper mostly introduces some influences of diamond wheel’s specialties on the grinding process and surface quality during ELID (electrolytic in-process dressing) grinding of hard and brittle materials. Research indicates that grain size and concentration of abrasive material should be reasonably selected based on the surface roughness. And Inhomogeneity of concentration distribution along wheel circumference will result in heterogeneity of insulator layer state, which will bring difference in the number of abrasive grain in the grinding area, thereby changing the actual cutting depth of every abrasive grain. Dynamic balancing of grinding wheel should be accurately adopted to reduce eccentric mass, furtherly to avoid generating waveness on the workpiece surface. For the purpose of reflecting rightly compositive effect from eccentricity of wheel shape, roundness of the wheel and periodical vibration derived from eccentric mass, actual radial runout of grinding wheel should be well and truly measured and controlled based on the wheel’s surface profile during wheel is rotating at working speed.

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Artefact in 20Å-Resolution Electron Images of Negatively Stained Twodimensional Membrane Protein Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053231 ◽

1982 ◽

Vol 40 ◽

pp. 92-93

Author(s):

Douglas L. Dorset ◽

Barbara Moss

Keyword(s):

Electron Scattering ◽

Cross Correlation ◽

Transmission Function ◽

Group Symmetry ◽

Asymmetric Structure ◽

Object Model ◽

Phase Object ◽

Computing Systems ◽

Resolution Electron ◽

Plane Group

A number of computing systems devoted to the averaging of electron images of two-dimensional macromolecular crystalline arrays have facilitated the visualization of negatively-stained biological structures. Either by simulation of optical filtering techniques or, in more refined treatments, by cross-correlation averaging, an idealized representation of the repeating asymmetric structure unit is constructed, eliminating image distortions due to radiation damage, stain irregularities and, in the latter approach, imperfections and distortions in the unit cell repeat. In these analyses it is generally assumed that the electron scattering from the thin negativelystained object is well-approximated by a phase object model. Even when absorption effects are considered (i.e. “amplitude contrast“), the expansion of the transmission function, q(x,y)=exp (iσɸ (x,y)), does not exceed the first (kinematical) term. Furthermore, in reconstruction of electron images, kinematical phases are applied to diffraction amplitudes and obey the constraints of the plane group symmetry.

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Application of cross correlation to HREM images of surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128080 ◽

1987 ◽

Vol 45 ◽

pp. 754-755

Author(s):

D. E. Luzzi ◽

L. D. Marks ◽

M. I. Buckett

Keyword(s):

Cross Correlation ◽

A Priori ◽

Matrix Material ◽

Correlation Method ◽

Accurate Knowledge ◽

Complex Image ◽

Fourier Filtering ◽

The Matrix ◽

Low Pass ◽

Data Reduction Technique

As the HREM becomes increasingly used for the study of dynamic localized phenomena, the development of techniques to recover the desired information from a real image is important. Often, the important features are not strongly scattering in comparison to the matrix material in addition to being masked by statistical and amorphous noise. The desired information will usually involve the accurate knowledge of the position and intensity of the contrast. In order to decipher the desired information from a complex image, cross-correlation (xcf) techniques can be utilized. Unlike other image processing methods which rely on data massaging (e.g. high/low pass filtering or Fourier filtering), the cross-correlation method is a rigorous data reduction technique with no a priori assumptions.We have examined basic cross-correlation procedures using images of discrete gaussian peaks and have developed an iterative procedure to greatly enhance the capabilities of these techniques when the contrast from the peaks overlap.

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