THE PREPARATION AND PERFORMANCE OF HIGH TEMPERATURE ADHESIVE CURED AT ROOM TEMPERATURE

High temperature adhesive bonding is one of the promising methods for joining carbon materials. A high temperature adhesive cured at room temperature was prepared by adding a curing agent of phosphoric acid to a mixture of phenol formaldehyde resin (PF) and boron carbide (B 4C). The graphite materials were bonded by the above adhesive and treated at different temperatures. Shear strength was tested at room temperature. Results showed that the high temperature adhesive cured at room temperature had satisfied bonding performance for graphite materials. The adhesive strength was larger than that for a thermally (200?℃) cured high temperature adhesive. In addition, the relation between adhesive performance and structure after being treated at different temperatures was also discussed. It revealed that the phosphoric acid condensed and converted into poly phosphoric acid during heat treatment and the chemical bond joining was introduced between the poly phosphoric acid and graphite matrix.