engleski

Corrosion behavior of Al foams in 0.5 M NaCl solution

The paper presents preliminary results of corrosion behavior of metal foam with different pore diameters as well as the reference alloy sample EN AC-AlSi9Cu3Fe in 0.5 M NaCl solution. Changes in an open circuit potential with time were monitored, polarization resistance and the potentiodynamic polarization curves were recorded, as well as mass change of samples was determined by the gravimetric method. The surfaces of the samples were recorded after examination with an optical microscope at a magnification of 50 and 100 times. The investigation results showed that higher porosity of the alloy leads to a decrease in the corrosion resistance of the alloy, which is manifested in a reduction of the value of polarization resistance and increasing the values of corrosion current. The gain in the mass of foam samples after gravimetric measurements in a time period of 168 h can be explained by the formation of the corrosion products in the pores of Al-foam samples which the ultrasonic treatment can not effectively remove after immersion in NaCl solution compared to the reference alloy sample.

metallic foams ; corrosion ; electrochemical methods ; gravimetric method

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