Joule heating enables ultra-fast SiC ceramics joining in seconds

Abstract

Reliable ultra-fast pressure-less joining of Silicon Carbide (SiC) ceramic is a critical challenge for extreme environment applications. This study presents a novel approach for ultra-fast, pressure-less joining of SiC ceramics. Utilizing the resistance increase owing to the interface reaction at the interlayer, an ultra-fast Joule heating technique enabled robust SiC joints in just 23 s without external preheating. A 5-micron-thick aluminum foil was used as the initial joining layer, undergoing a rapid interface reaction to generate high-resistance compounds, such as Al₄C₃, Al₄SiC₄, and Al₂OC during the flash heating process. This localized heating, which inhibited the energy dissipation in heating the entire joint assembly, facilitated the creation of strong SiC joints within seconds without pre-heating, achieving a shear strength up to 76 ± 12 MPa. The proposed joining method, utilizing the inherent resistance changes within the interlayer, demonstrates significant potential for joining other non-conductive ceramics effectively.