Effect of Nanosilica and Boron Carbide on Adhesion Strength of High Temperature Adhesive Based on Phenolic Resin for Graphite Bonding

In this study, the effect of nanosilica and boron carbide on the adhesion strength of a phenolic resin for graphite bonding was studied. The adhered specimens were cured at 250 degrees C and then heat treated to examine the thermal resistance in the range 200-1000 degrees C. Then, the adhesion strength of specimens was examined by a tensile method. The chemical structure of bonding and possible carbonization was examined using Fourier transform infrared spectroscopy (FTIR). Thermogravimetric analysis (TGA) was employed to determine the char yield, and X-ray diffraction (XRD) was used to study crystalline phases at different temperatures. The elemental analysis and morphology of the adhesive bond were investigated using energy-dispersive Xray spectroscopy (EDS) and scanning electron microscopy (SEM), respectively. The results showed that sintering of reformed boron carbide and amorphous carbon above 800 degrees C resulted in a significant increasing in adhesion strength at 1000 degrees C.