Stirring assisted brazing of SiC（p/A356） composites in air was investigated. A stirring was applied on one of the samples to be bonded at 455℃ during brazing. The filler metal was extruded and impacted intensively ...Stirring assisted brazing of SiC（p/A356） composites in air was investigated. A stirring was applied on one of the samples to be bonded at 455℃ during brazing. The filler metal was extruded and impacted intensively on the two surfaces of the base materials during stirring. It can be found that oxide film on the surface of the composites can be disrupted and removed through the observation by scanning electron microscopy （SEM）. The metallurgical bonds formed between the filler metal and the base materials. However, continuous residual oxide film was found at bottom joint interface, which limited the lift of joint strength. A stirring was applied once more after the samples were continuously heated up to 470 and 500℃, respectively. At this time, residual oxide film after the first of stirring can be broken by once more stirring. The bonds are mainly composed of a new alloy, which have a higher content of aluminum and are free of continuous oxide film, showing higher shear strength of 113 MPa than that of the base materials.展开更多
基金supported by the National Natural Science Foundation of China (No. 50975303)the Natural Science Foundation Project of CQ CSTC, China (No. cstc2011jjA50001)the State Key Lab of Advanced Welding and Joining, Harbin Institute of Technolog, China (No. AWPT-M12-07)
文摘Stirring assisted brazing of SiC（p/A356） composites in air was investigated. A stirring was applied on one of the samples to be bonded at 455℃ during brazing. The filler metal was extruded and impacted intensively on the two surfaces of the base materials during stirring. It can be found that oxide film on the surface of the composites can be disrupted and removed through the observation by scanning electron microscopy （SEM）. The metallurgical bonds formed between the filler metal and the base materials. However, continuous residual oxide film was found at bottom joint interface, which limited the lift of joint strength. A stirring was applied once more after the samples were continuously heated up to 470 and 500℃, respectively. At this time, residual oxide film after the first of stirring can be broken by once more stirring. The bonds are mainly composed of a new alloy, which have a higher content of aluminum and are free of continuous oxide film, showing higher shear strength of 113 MPa than that of the base materials.
