Grinding liquid for processing surface curvature radiuses of sapphires and preparation method

Abstract

The invention relates to a grinding liquid for processing surface curvature radiuses of sapphires and a preparation method. The grinding liquid is composed of grinding paste and a dispersion liquid with the weight proportion of 1:20, wherein the dispersion liquid comprises kerosene and vegetable oil with the weight proportion of 5:1, and the grinding paste comprises 80-100 parts of diamond micropowder, 4,000-5,000 parts of stearic acid, 200-500 parts of kerosene, 1-3 parts of ferric nitrate and 0.5-3 parts of phosphoric acid by weight. By adopting the grinding liquid in the invention for the fine surface curvature of a major-diameter sapphire lens, an obtained product has high surface quality, the processing state is stable, and requirements on subsequent polishing can be met; and moreover, the grinding liquid has the advantages of high processing efficiency, low cost and wide processing range.

Description

technical field [0001] The invention relates to a grinding liquid used in the surface finishing process of the radius of curvature of a large-diameter sapphire lens, in particular to a grinding liquid used for processing the radius of curvature of a sapphire surface and a preparation method thereof. Background technique [0002] Artificial sapphire lens has the characteristics of good light transmission, high hardness, wear resistance, small linear expansion coefficient, high compressive strength and acid and alkali corrosion resistance, and is widely used. However, because artificial sapphire has high hardness (Mohs scale 9), high brittleness, crystal anisotropy and other characteristics, its processing is also quite difficult, especially the processing of the radius of curvature surface of the sapphire lens is required for high precision and high finish. [0003] At present, the surface finishing of the radius of curvature of the sapphire lens mainly adopts diamond micropo...

AI Technical Summary

Problems solved by technology

[0005] ① If the threshing property of the abrasive tool bond is increased, this phenomenon will be reduced to a certain extent, but due to the increase in the threshing property of the abrasive tool, the wear rate of the abrasive tool will be accelerated, and the processing axis line will occur due to the loss of the abrasive tool. Displacement deviation, so that the value of the radius of curvature of the lens changes continuously

When the situation is serious, it will cause processing defects such as out-of-tolerance lens curvature radius, "top" and "top convex", and the machine tool must be readjusted

In this way, the radius of curvature of the sapphire lens is constantly changing during the processing process. In severe cases, multiple radii of curvature will be formed on one surface, resulting in a serious out-of-tolerance profile of the curved surface of the sapphire lens.

[0006] ②If the grinding time is prolonged or the grinding pressure is increased, the grinding layer of the grinding ring is prone to clogging when processing with resin abrasive tools

The gem powder is embedded in the bond gap of the grinding ring, so that it can neither be ground nor chipped

At this time, if the grinding layer is ground, it will easily cause the curvature radius of the lens to be out of tolerance, the center displacement will be offset, and defects such as protrusions and loops will appear in the center of the lens.

[0007] In summary, the use of diamond micropowder resin bonded abrasives for finishing the curvature surface of large-diameter sapphire lenses has low efficiency and unstable processing conditions, and at the same time seriously affects the subsequent polishing process

Images