A Three-Dimensional Model for the Surface Texture in Surface Grinding, Part 2: Grinding Wheel Surface Texture Model
In order to produce ground parts that have desirable surface properties, it is necessary to understand the evolution of these characteristics through the surface generation mechanisms involved in the grinding process. Since the geometry of the wheel surface, in part, determines the final workpiece geometry, the influence of the 3-D structure of a wheel surface on the final workpiece geometry is studied. In this work, a wheel surface model is developed that can be integrated with a surface grinding process model for simulating workpiece surface texture. The simulations utilizing the integrated model are used to study the workpiece surface roughness as a function of the frequency characteristics of the wheel surface. The 2-D Fourier forward and inverse transforms are employed to study and model the 3-D surface structure. In particular, the effect of specific frequency components in the wheel surface on the ground surface are analyzed. It is shown that workpiece surfaces resulting from wheel surfaces with dominant low frequency components have higher roughness, and that the low frequency components indicate a clustering of abrasive grains on the wheel surface. @DOI: 10.1115/1.1391428#
Roughness Generation In Precision Grinding Of Small Optical Surfaces
Small steel moulds for injection moulding of polymer lenses are precision ground at Philips Research Laboratories. As part of a broader research program the relations between the process parameters and the generated surface roughness are investigated. A computer simulation technique used to investigate these relations is described. This technique allows us to investigate the effects of grinding wheel and workpiece geometries and of grain size, distribution and concentration. Process parameters such as depth of cut, infeed, and angular velocities can be chosen. The effects of initial workpiece roughness and of multiple passes of the grinding wheel over the surface can be investigated. Unbalance of the grinding wheel can also be taken into account. A simple geometrical model is used to calculate the shape of the scratches made by grains engaging the workpiece. The wear behaviour of grains can be taken into account assuming a simplified wear law. Some results of these simulations are presented. Predicted trends are compared with experimental results.
Filtering of surface profiles using fast fourier transform
Abstract An essential preliminary to numerical assessment of roughness is the elimination of waviness. The waviness is usually filtered using analog filters of the capacitance-resistance type. This paper deals with a digital technique to remove the waviness. FFT, one of the important tools of digital signal processing was used to filter surface profiles. This technique was compared with the existing methods available for filtering surface profiles.