The Relationship between Phase Structure and Melting Characteristics of High Cesium Content KF-CsF-AlF₃ Aluminum Flux

Abstract:

The melting curves of high cesium content KF-CsF-AlF3 flux samples prepared by the wetting synthesis method were measured by differential scanning calorimetry (DSC), and the effect of the flux compositions on the melting characteristics was analyzed and summarized. Existing phases of every representation sample was identified by X-ray diffraction (XRD), meanwhile, the morphology and chemical elements of the typical flux samples were analyzed by scanning electron microscope (SEM) and energy spectrum analysis (EDS), respectively. The results indicated that solid phase decomposition first occurred in the common phase Cs2AlF5 for all the flux samples at 420°C; one of the decomposition products, Cs3AlF6 take the eutectic reaction with the Cs2KAlF6 at about 450°C; the flux samples containing phase CsAl2F7 or Cs2KAl3F12 have the e5 and e1 eutectic reaction at 471°C and 525°C, respectively, and their liquidus increased correspondingly. The liquidus for regionⅠflux samples is about 450°C and with a narrow melting range, which would make them good substrates for aluminum alloy middle temperature brazing.

• Periodical: Advanced Materials Research (Volumes 634-638)
• Pages: 2909-2915
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.634-638.2909
• Online since: January 2013
• Authors: Fang Jie Cheng, Jun Xiang Yang, Hai Wei Zhao, Guan Xing Zhang, Jun Lan Huang, Wei Min Long
• Keywords: KF-Csf-Alf3 Flux, Melting Characteristics, Phase Structure, Wetting Synthesis Process

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