Profile Characterization of Manufactured Surfaces Using Random Function Excursion Technique, Part 2: Application

Abstract

In Part 1 of this paper an analytical procedure based on the theory of random excursions was described to characterize the texture of a machined surface in terms of four new parameters. In this part a number of experimental results are presented to justify the validity of the proposed surface parameters. Surface measurements were carried out on ten differently machined surfaces using a specially equipped measuring device with a direct cable link to a hybrid computer. The theoretically computed surface parameters compare favorably with the measurements made on the actual surface profiles that were recorded experimentally. One of the advantages of the surface parameters presented in this paper is that they correspond directly to the mechanical properties of the machined component and hence can be used readily in specifications. Further, the results of this paper show that i) the sampling length is essentially a high-pass filter with geometrically defined characteristics, and ii) the crest and valley excursion parameters are adaptable for both “on-line” and “off-line” surface evaluation. The method presented is well-suited for application to computer-aided manufacturing without any special modifications. Based on this investigation, a proposal for a mechanical stylus system for “online” surface measurements is also made.