Comparative Study on the Activity of GaF<sub>3</sub> and Ga<sub>2</sub>O<sub>3</sub> Nanoparticle-Doped CsF-AlF<sub>3</sub> Flux for Brazing 6061 Al/Q235 Steel Joints

oleh: Zhen Yao, Songbai Xue, Junxiong Zhang

Format: Article
Diterbitkan: MDPI AG 2020-06-01

Deskripsi

The effect of trace amounts of GaF<sub>3</sub> and Ga<sub>2</sub>O<sub>3</sub> nanoparticles on the wettability and spreadability of CsF-AlF<sub>3</sub> flux matched Zn-15Al filler metal were comparatively studied on 6061 aluminum alloy and Q235 low-carbon steel. The experimental results indicate that appropriate amounts of GaF<sub>3</sub> and Ga<sub>2</sub>O<sub>3</sub> added into the flux could significantly promote the Zn-15Al filler metal to wet and spread on the surface of 6061 aluminum alloy and Q235 low-carbon steel. The optimum ranges for GaF<sub>3</sub> and Ga<sub>2</sub>O<sub>3</sub> were 0.0075–0.01wt.% and 0.009–0.01 wt.%, respectively. Comparative analysis showed that the activity of CsF-AlF<sub>3</sub> flux bearing GaF<sub>3</sub> was higher than that bearing Ga<sub>2</sub>O<sub>3</sub>. The reason for this is that the former flux has a stronger ability to remove oxides of the base metal and reduce the interfacial tension of the molten filler metal and the base metal.