The high-temperatures bonding of graphite/ceramics by organ resin matrix adhesive

The joining of ceramic materials is one of the key factors that influence its successful application in wider fields. And the joining between different kinds of materials has more values and significances in the realistic society. In this paper, graphite/alumina ceramic joints were achieved by means of bonding method. A high-temperature adhesive was prepared by using phenol–formaldehyde resin as matrix and boron carbide (B4C) as additive. The graphite/alumina joints were bonded by the above adhesive and treated at different temperatures. The adhesive strength was tested at room temperature. Results showed that the high-temperature adhesive possessed satisfactory adhesive property for the joining of graphite/ceramics (Al2O3). The adhesive strength of the joints treated at 600 °C and 800 °C was not satisfactory due to the decline of the cement framework, which was derived from the carbonization of the resin. But good adhesive strength and thermal shock resistance were achieved when the treat temperature was above 1000 °C. As to the test of thermal shock resistance, the adhesive strength of the joints decreased at the beginning and then was stabilized and rose again after experiencing several shock cycles. By means of scanning electron microscope (SEM), the micrograph of bonding interface was investigated and showed that the failure mode of joint was due to the mixing failure. Ceramic substrates could be found on the bonding interface due to the high bonding force.