Diffusion bonding of silicon carbide components - via heat and pressure producing gas-tight joints withstanding high temps. and corrosion

摘要

The components consist of SiC which has been infiltrated with Si, or reaction-bonded SiC; and they are joined together by diffusion bonding in vacuo or a protective gas atmos. The joints obtd. are mechanically stable at up to ca. 1400 deg.C; gastight; and resistant to corrosion or oxidn. The joints are pref. made by a combined diffusion-reaction welding process, using an intermediate layer (I) between the joint surfaces. Layer (I) is pref. Si; a metal alloy contg. Si; Si contq. B or Al; or a mixt. of Si and colloidal carbon. Layer (I) can be applied via powder spraying; thermal decompsn. of a soln.; sputtering; evapn.; or electrodeposition.