Low-thermal expansion ceramics bonding body and manufacturing method of the same

摘要

A bonded body obtained by unifying a plurality of structural members exhibiting 0.6*10^-6/K or less of absolute value of thermal expansion coefficient in room temperature, 100 GPa or more of modulus of elasticity and 40 GPa.cm³/g or more of specific rigidity, the plurality of structural members having bonding surfaces that are brought into contact with each other and are unified by a heating process, and a manufacturing method thereof are provided. The sintered block contains 51.5 to 70.0 oxide-equivalent mass % of Si, the oxide-equivalent mass % being calculated as a ratio of Si in elements (Mg, Al and Si) constituting the sintered block on oxide (MgO, Al₂O₃, SiO₂) basis. Surplus SiO₂ residing in the sintered block forms a liquid phase during the heating process to activate mass transfer, so that the material of the bonded portion becomes substantially the same as the base material. Residual stress on account of difference in thermal expansion coefficient can be eliminated and a bonded body with extremely high bonding strength can be obtained.