ABSTRACT
SierracladTM samples of clad 8-polycarbonate-Clad 8 were tested for crazing using Mil-P-25690A. Fusion-bonded acrylic/polycarbonate composites shattered at 75 ft-lbs. Certain SierracladTM composites were impact resistant as monolithic polycarbonate. The name “Sierraclad” was given to the concept of rigid polyurethane facings adhering to polycarbonate. The engineering project discussed involves the development of protective rigid polyurethane cladding for F-15 polycarbonate canopies. A team of engineers worked on this project for many months. Some of them specialized in forming canopies and windshields with the new materials. The F-15 airplane was designed to fly very fast and low to the ground in order to avoid enemy radar detection. The original F-15 canopy was formed from acrylic plastic, but it was discovered that acrylic canopies were far too fragile for this application. Sierracin was producing polycarbonate canopies for the F-15 aircraft and they had developed a special process for protecting their surfaces from an abrasion and hostile chemicals.
