Detection of Gases Generated from Si3N4-Based Ceramics during the Fracture Test under Ultra-High Vacuum

Three types of Si3N4-based sintered ceramics were fractured in an ultra-high vacuum and the gases generated during the fracture were analyzed by quadrupole mass spectroscopy. Various gases such as H2, CH4, N2, CO, Ar and CO2 were detected after the fracture event in all the materials. The emission peak intensities of the gases and the total pressure changes in the chamber depended on the types of materials, but the gas compositions were similar to each other. These gases are thought to be released mainly from residual pores formed during sintering. Some of the gases may be produced at the moment of fracture. This method is expected to be applied to fundamental studies on the processing and fracture of advanced ceramics.