Study of deoxidation of 2024-T3 with various acids

Abstract

Sheet aluminium 2024-T3 alloy was treated in a range of acid solutions. These acid solutions included HNO 3 , H 2 SO 4 , and H 3 PO 4 alone, with HF, and with a combination of the oxidant sodium persulphate (Na 2 S 2 O 8 ) and HF. Changes in the surface chemistry and morphology of the matrix and intermetallics were characterised by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS), Rutherford backscattering spectroscopy (RBS), and X-ray photoelectron spectroscopy (XPS). Etch rates for each acid solution were determined by weight loss after repeated immersion. In addition, the acid solutions were analysed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) to determine the amount of aluminium and alloy component dissolution.MST/4948

Effects of different surface cleaning procedures on the superficial morphology and the adhesive strength of epoxy coating on aluminium alloy 1050

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Development of cerium‐based conversion coatings on 2024‐T3 Al alloy after rare‐earth desmutting

“…No associated features could be detected in x-ray maps of the surface, although 24 observed Cu enrichment at the metal/oxide interface in anodized coatings and Hughes et al 25 observed Cu enrichment in the thin surface oxide remaining after desmutting of AA2024-T3 in HNO 3 /HF desmutters. Thus, thinning of the surface oxide on the ridge of the rolling marks may expose cathodic material, which promotes H 2 O 2 reduction and ceria deposition.…”

Non-chromate deoxidation of AA2024-T3 using Fe(III)-HF-HNO3

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