This study investigated the effect of laser texturing parameters on the shear strength and microstructure of SiC ceramic joints, which were joined using CaO-Al 2 O 3 -MgO-Y 2 O 3 -SiO 2 (CAMYS) glass filler. It was demonstrated that laser texturing promotes the formation of SiO 2 on the surface and subsequent filler adhesion. Groove depth and spacing were identified as critical factors for joint performance. Excessive groove depth (∼60 μm) caused incomplete groove filling and reduced joint strength, due to void formation. Similarly, decreased texturing spacing (∼200 μm) induced excessive thermal damage and compromised joint robustness, as observed in laser-treated ceramic surfaces. Among the five evaluated texturing configurations, the optimal condition, defined by a groove depth of ∼30 μm and spacing of ∼500 μm, yielded a maximum shear strength of 80 ± 12 MPa, representing a 77.8 % improvement over untextured joints (45 ± 10 MPa).
Rechargeable magnesium batteries (RMBs) have garnered significant attention in recent years. However, the commercialization of RMBs has been severely hampered by the low-strength and high-resistance connections between the magnesium (Mg) anodes and aluminum (Al) tabs. To address this challenge, we perform orthogonal experiments on 0.2 mm-thick Al–Mg ultrasonic welded joints to establish an optimized parameter range. Analysis of variance revealed that ultrasonic amplitude exerted the most dominant influence on joint strength (52.03%), followed by welding time (25.59%) and welding pressure (22.37%), with a significant interaction effect observed between welding time and amplitude. Notably, at a welding pressure of 0.40 MPa, the Al–Mg joint achieved peak performance, including the maximum lap-shear load (59.20 N) and minimal electrical resistance (0.483 mΩ). RMB pouch cells assembled with good-welded tabs demonstrated superior electrochemical performance compared to under and overwelded counterparts, exhibiting reduced internal resistance (3.55 Ω in the first cycle), enhanced capacity retention (77.45% after 60 cycles), and raised Coulombic efficiency (99.88% after 440 cycles).
Jiangang Chen,Meixia Cai,Ying Liu,Panpan Yang,Jiping Wang
This paper develops a novel adhesive for in-situ joining C/C composites to C/C-SiC composites using a phenolic resin modified with inert fillers (SiC and graphite powders). The primary phase of the reaction bonding joint layer is SiC, which matches the thermal expansion coefficient of the matrix better than metallic phases, making it an improvement over traditional brazing. The effect of filler content on joint strength, oxidation resistance, and thermal shock resistance has been systematically investigated. The results show that increasing the filler content from 0 to 50 wt% increases shear strength up to a maximum of 25.97 MPa at 15 wt% SiC and 15 wt% graphite powder. The oxidation and thermal shock tests reveal that the joints exhibit a decrease in shear strength due to oxidation at temperatures above 600 °C, with a significant reduction occurring between 600 °C and 700 °C. After seven thermal shock cycles at 800 °C, the shear strength of the joints remains relatively high, indicating the good thermal shock resistance of the bonding layer. The method proposed in this study provides a new approach for controlling residual silicon and enhancing the properties of C/C-SiC joints.