Beryllium surface preparation

A number of prebonding surface preparations for bonding beryllium and its alloys with epoxy adhesives have been suggested in the literature. One procedure is to degrease the substrate with trichloroethylene, followed by immersion in the solution listed below for 5 to 10 min at 23°C. 

The substrate should then be washed in tap water and rinsed with distilled water. The final step in the process is an oven-dry of 10 min at 121 to 177°C.26 Several other surface preparation procedures for beryllium have been reported to have merit. Epoxy and epoxy hybrid adhesives have been found to provide high strengths on sulfuric acid-sodium dichromate etched beryllium.27... 

Cagle, C. V., Surface Preparation for Bonding Beryllium and Other Adherends, in Handbook of Adhesive Bonding, C. V. Cagle, ed., McGraw-Hill, New York, 1973. 

Cagle, Surface Preparation for Bonding Beryllium and Other Adherends. ... 

Beryllium-copper bellows have typically been joined by applying a two-part epoxy and accelerating the cure with heat. A single-component structural UV-aerobic acrylic performs the same operation in 30 seconds with the added advantage of having eliminated surface preparation. 

Cagle CV. Surface preparation for bonding beryllium and other adherends. In Cagle CV, ed. Handbook of Adhesive Bonding. New York, NY McGraw-Hill 1973. 

The hob or a master model is usually made of a good quality, hardened steel. Its face is machined to the exact size and contour of the reproduction desired. All surfaces of the hob are highly polished after hardening. The blanks for the impressions are made from soft steel (or beryllium-copper) and are prepared by grinding and polishing the surface that is to come in contact with the hob. Depending on the size and the contour of the hob, it is advisable to remove some of the material from the bottom of the blank. After preparation the blank is placed in a hydraulic press, and the hob is placed in position over the blank before the press is closed. The actual hob pin is done in the press at a very slow rate of speed. The pressure required for hobbing varies from 50 to 150 tons/in of die impression. 

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