氟铝酸钾焊接助溶剂对汽车散热器翅片腐蚀行为的影响

Flux Effect on Corrosion of Aluminium Heat Exchanger Fin Materials

采用扫描电镜和动电位极化实验研究氟铝酸钾焊接助溶剂对加热后翅片的微观结构及其在0.6 mol/L NaCl(pH6)溶液中腐蚀行为.结果表明氟铝酸钾焊接助溶剂提高了加热后翅片材料的阳极活性,但却降低了阴极活性.

Flux was used during the brazing of aluminium heat exchanger fin and then the residual of flux enriched K and F may affect the corrosion performance of the aluminium alloy,therfore,the effects of flux on the corrosion behavior of fin materials have been studied in 0.6 mol/L NaCl solutions by SEM and potentiodynamic polarizations.The results indicate that the fluxed surface shows a significantly lower cathodic reactivity than the bare surface without flux,because the flux was found to form a plate-like and needle-like structure on the surface.It is likely that the layer of flux acts as a diffusion barrier,suppresing the penetration of oxygen to the aluminium alloy surface.