High Sensitivity Shrinkage Test for Adhesives
Original Publication Date: 1987-Apr-01
Included in the Prior Art Database: 2005-Feb-01
The use of adhesives (e.g., epoxies) often provides an economical method for assembling components, but if positioning accuracy is very important, the curing of the adhesive must occur with minimum shrinkage. Here are some ways to compare the shrinkage of various adhesives. In Fig. 1, a wedge-shaped space is formed between a glass base plate 5 and cover plate 8. An elastomer spacer 7 may be used to support one side of the cover. The wedge-shaped space is filled with (Image Omitted) uncured adhesive 9, and the angle between the two plates is measured by using, for example, an autocollimator or other optical system. A simplified optical schematic is shown: Incoming ray 1 partially reflects from base 5 and exits as ray 4, striking plate 6 and forming spot 10.