Metrological analysis of measurements of elastic deformations in the contact zone of spherical corundum of the tips with the surface of the product

Abstract

Abstract The article analyzes indirect measurements of elastic deformations of ld during video recording of the contact zone between the corundum spherical tip and the surface of the product. These measurements are due to the need to compensate for elastic deformations ld to improve the accuracy of contact measurements of the dimensions of the products characteristic of all measuring instruments: coordinate measuring machines, active control devices and other devices. The method of measuring elastic deformations ld is similar to the measurement of Brinell hardness, but with a small clamping and immersion in the product of a spherical tip made of high-strength optically transparent material and the implementation of on-line visualization and video recording by a built-in measuring microscope of the formed control zone. Determined the sensitivity of this method, non-linear related to the radius of the spherical tip, Rtip and elastic deformations ld. The obtained expression for the measurement error of the deformations Δld that largely depends on thermal expansion of the tip ΔRtip(ΔT) and the registration error of the zone control Δlzc.