Mechanical comparison calibration of gauge blocks using reference standards that are a different material from the client gauge block can be problematic. This two-part study investigates some of the dominant influences identified in the mechanical comparison calibration of ceramic gauge blocks using steel reference standards. The goal is to develop techniques for lowest uncertainty mechanical comparison calibration in the application of two dissimilar gauge block materials. Of primary interest are: correction for differences in mechanical stylus deformation, and length equivalent thermal corrections in the different materials. In our model, mechanical stylus deformation is evaluated using gauge blocks of known length, calibrated by optical interferometry. The optical phase correction applied in this initial interferometric determination of gauge block length is an important first step. In the first part of this study, optical phase correction for ceramic gauge blocks has been determined using similar techniques by three labs, all of them applying the method of stack experiments using the same gauge blocks, and similar platens. One of the platens is of the same material and made by the same manufacturer as the ceramic gauge blocks. Temperature effects dominate the mechanical comparison calibration of dissimilar materials. In the second part of this study, the importance of the approach to length corrections as a result of temperature variation is demonstrated.

Date Published: 22 October 2001
PDF: 10 pages
Proc. SPIE 4401, Recent Developments in Traceable Dimensional Measurements, (22 October 2001); doi: 10.1117/12.445628

Published in SPIE Proceedings Vol. 4401:
Recent Developments in Traceable Dimensional Measurements
Jennifer E. Decker; Nicholas Brown, Editor(s)