Characteristics of dynamically-formed surface oxide layers on molten zinc–aluminum alloys: A multimodality approach

Influence of the Anodization Process on Zamak 5 Corrosion Resistance

“…Aluminum presents on both the outer surface and the inside of the coating appears to give rise to a thick Al 2 O 3 film and consequently to make the surface hydrophobic. In the case of Zatv, the sample was dried after being electrolytically degreased, which justifies the behavior similar to that of the ZP sample, with the preferential formation of Al 2 O 3 in air 27,28 .…”

“…It can be seen, Figure 9, that the ZP and Zatv samples showed more noble and less noble behavior, respectively, in relation to Zatv-30-G. ZP's most noble behavior with respect to Zatv may be due to the aluminum contained in zinc, forming an air-protective layer of Al 2 O 3 27,28 . The ZP sample has a smaller cathodic Tafel slope compared to the other samples, indicating that the corrosion current is limited by the diffusion rate 30 .…”

“…The ZP sample, Figure 12b, presents, in 1h of immersion, three time constants, at high, medium and low frequency. The high frequency phenomenon can be associated with aluminum oxide formed instantly in air 28 . According to Liu et al 33 and Cao et al 27 , the first high frequency time constant refers to the properties of the corrosion product layer, which in this case is due to air-formed Al 2 O 3 .…”

Contemporary Progresses in Ultrasonic Welding of Aluminum Metal Matrix Composites

“…And alumina is a bane for a fundamental reason, as we know that alumina has a higher temperature than pure Aluminum. Alumina removal-related technology has been tested using ultrasonic cavitation or by addition of Sodium Hydroxide (Dimitescu et al, 2018;Mehrabian et al, 2018;Nayebi et al, 2018;Long et al, 2019;Park et al, 2019). But even if implemented, current industries can potentially face more cost in manufacturing Aluminumbased components and removing alumina.…”

Influência do Nb contido em eletrólito a base de oxalato na anodização de alumínio em ácido oxálico

“…As amostras não anodizadas, "Al-Pura-D" e "Al-Pura-SD", são as que apresentam maior valor de ângulo de contato, 105,25º e 91,1º, respectivamente, apresentando uma característica superficial hidrofóbica, ou seja, sem espalhamento do líquido, fazendo com que o líquido não molhe o sólido (Luz, et al, 2008). Essa característica hidrofóbica é consequente da velocidade de formação do óxido de alumínio (Al2O3) na superfície, o qual é formado preferencialmente em contato com o ar (Cao, et al, 2017;Mehrabian, et al, 2018), o mesmo ocorre com outros óxidos e essa característica também é atribuída à diminuição da energia livre superficial (Albuquerque, et al, 2014). De acordo com Kesong et al, 2013, as amostras que não foram anodizadas apresentam uma resistência à corrosão acima das que foram anodizadas devido ao caráter hidrofóbico apresentado.…”