Qualification Based on Heritage Data

Some adhesives have been used successfully for over 20 years in specific applications and environments, and aieliability database is available (heritage data). These adhesivesmay thusbe qualified forother applications by similarity of exposure and operating conditions. In general, the adhesive may be qualified and used if it had previously been used successfully in a proven, equivalent application for which the environmental conditions and tests were at least as severe as those required of the candidate application. 

Reliability data are available for many adhesives used in space environments fordifferentorbits, different radiation, anddiffeientthermal-vacuum conditions. These data are available from approved materials and processes lists from NASA i or from contractors for programs such as the Space Shuttle, Space Station, GPS, Hubbel telescope, and numerous satellite systems, some of which have been in orbit for over ten years. Adhesives used in military electronics have also been proven highly reliable in fighter planes, navy ships, ground and air communication systems, and navigation systems. 

The reliability of silver-filled epoxy adhesives, such as Ablestik s Ablebond 36-2 and 84-1, and Epoxy Technology s Epo-Tek H20, and of insulative adhesives such as Emerson and Cuming s Eccobond 104 and Ablestik s Ablebond 84-3, has been demonstrated through many years of use in military, space, and medical electronics. During the period of 

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