Mikro-ark oksidasyon yöntemi ile oksitlenen 2017A alüminyumun erozyon-korozyon direncinin incelenmesi

2017A alüminyumu belli boyutlarda kesilmiþ ve mikro ark oksidasyon (MAO) yöntemi kullanýlarak yüzey modifikasyonu gerçekleþtirilmiþtir. Yüzeyinde seramik bir oksit tabakasýnýn oluþtuðu alüminyum; oda sýcaklýðýnda, farklý sürelerde, HCl çözeltisi ve Al2O3 toz parçacýklarýnýn manyetik karýþtýrýcý yardýmýyla karýþtýrýldýðý erozif-korozif bir ortama maruz býrakýlmýþtýr. Mikro-ark oksidasyon ve erozyon-korozyon deneyleri öncesi ve sonrasýnda numunelerin kütle ölçümleri yapýlmýþ ve XRD yardýmýyla faz analizleri gerçekleþtirilmiþtir. Ayrýca numunelerin optik mikroskop ile yüzey görüntüleri elde edilerek, erozif-korozif ortamýn numunenin yüzeyinde meydana getirdiði deðiþim irdelenmiþtir. Çalýþma sonucunda 2017A alüminyumunun Mikro-ark oksidasyon ile yüzeyinin kaplanmasý ile erozyon-korozyon direncinde belirgin bir artýþýn elde edildiði tespit edilmiþtir. Özellikle MAO iþlem süresini 5 dk. dan 45 45 dk. ya çýkartmakla kaplama kalýnlýðýnda yaklaþýk 6 kat artýþ elde edilmiþtir. Bunun neticesinde 3 h lik erozyon-korozyon deneyinde kütle kaybý % 40.2 den % 0.7 ye düþürülerek erozyon-korozyona karþý dayaným yaklaþýk 60 kat arttýrýlmýþtýr.

Investigation of erosion-corrosion resistance of 2017A aluminium oxidized by micro-arc oxidation process

2017A aluminium sample was cut into certain pieces and surface modification was practiced via micro arc oxidation (MAO) method. Aluminum alloy, on the surface of which a ceramic layer was formed, was exposed to an erosive-corrosive environment at room temparature for different times. During the exposure Al2O3 powder particles were stirred in HCl solution. Mass measurements and XRD phase analyses of the samples were taken before and after the micro arc oxidation process and erosion-corrosion experiment. In addition, surface images of the samples were taken by optical microscopy in order to examine the changes in the surfaces of the samples produced by erosive-corrosive environment. As a result of this study, it was also determined that an obvious increase in erosion-corrosion resistance of 2017A aluminum oxidized by micro arc oxidation process occured. In particular, by extending the MAO processing time from 5 min to 45 min, an increase of about 6 times in coating thickness was obtained. As a result, in the 3 h erosion-corrosion test, the mass loss was reduced from 40.2 % to 0.7 % and so the erosion-corrosion resistance was increased about 60 times.