Surface Modification of Titanium by Atmospheric Pressure Plasma Treatment for Adhesive Bonding and Its Application to Aviation and Space

Titanium is one of the most effective materials for structural application of space craft and aviation. Titanium alloys are widely used in solid rocket booster cases, guidance control pressure vessel and other different applications demanding light weight and reliability. Aerospace industry is also a larger market for titanium products and adhesive bonding is advantageous in terms of its fabrication. However, surface treatment of titanium alloy is critical in improving the adhesive bond strength and long term durability of the adhesive joint. In this investigation surface treatment of titanium is carried out by plasma ion implantation in order to increase adhesive bond strength and durability. Optical microscopic and SEM analysis of untreated and atmospheric plasma treated specimens is carried out to examine the surface characteristics. A substantial improvement in the surface energy of Titanium is observed after the atmospheric plasma treatment. The Treated surface was basically characterized by contact angle analyzer for the activation property on the surface. The surface energy of titanium surface increases with increasing exposure time of atmospheric pressure plasma. The optimized time of plasma treatment suggested in this investigation results maximum adhesive bond strength with polyimide adhesive and consequently, this technology is highly acceptable for aviation and space applications