In this study, the hot corrosion of TiAl, TiAlNb, and Ti3AlNb intermetallics with or without enamel coating and sputtered TiAlCr coating in (Na, K)2SO4 + NaCl melts at 750oC is investigated. The interfacial reaction between enamel and those alloys during hot corrosion has also been evaluated. The results indicate that severe corrosion of bare alloys occurs due to the self catalysis chlorination...

Galvanic Corrosion and Composites. “Galvanic corrosion is an electrochemical process in which one metal corrodes preferentially when it is in contact with a different type of metal and both metals are in an electrolyte [1].” Thus, corrosion of this type is always a concern when two different materials are to be in mutual contact. In the aerospace industry for instance, galvanic corrosion could ...

A time–frequency analysis-based signal processing study for detecting active corrosion in aluminum plate-like structure utilizing the broadband piezoelectric wafer active sensors is presented in this article. Tests were conducted on an aluminum plate with a network of sensors installed on one side of the plate for Lamb wave generation and reception. The corrosion was emulated as material loss o...

Corrosion is a natural process that seeks to reduce the binding energy in metals. The end result of corrosion involves a metal atom being oxidized. Surface corrosion on aluminum aircraft skins, near joints and around fasteners, is often an indicator of buried structural corrosion and cracking In this paper we proposed a new method on which we are moving towards designing a method to detect the ...

In order to improve the corrosion resistance of aluminosilicate refractories by molten aluminum, alkaline fluoride NaF and cryolite Na3AlF6 powders were studied. Both physical and chemical properties are known to influence wetting and corrosion behavior. This paper devoted to determine the influence of alkaline fluoride and cryolite added to andalusite based castable on the reaction with a...

In this study the Taguchi method, has been applied to optimize the heat treatment parameters for the corrosion resistance of AA6061 aluminum alloy. The experimental design consisted of four parameters (aging temperature, aging time, quenching environment and NaCl concentration), each containing three levels. Tafel polarization measurements were carried out to determine the corrosion resistance ...

Caustic stress corrosion cracking has only been superficially examined in aluminum alloys. In caustic (basic) environments, the inherent, protective oxide layer becomes soluble on aluminum and allows for further degradation. The purpose of this study is to observe the effect of a strong base solution (sodium, hydroxide, sodium hypochlorite, sodium silicate, pH ~12) on the strength and stress-st...

plasma electrolytic oxidation (peo) was performed on a 1010 aluminum alloy. to achieve thenanocomposite structure, si3n4 nanoparticles were added into the electrolyte. in an alkaline aqueoussuspension (silicate-based), the effect of adding niso4 on the applied voltage, microstructure,composition, wear, and corrosion resistance of peo coatings was investigated using scanningelectron microscopy (...

In this paper, we present a multiple mode sensing methodology to detect active corrosion in aluminum structure utilizing the broadband piezoelectric wafer active sensors. This method uses ultrasonic Lamb wave complemented with the electromechanical impedance measurement to detect, quantify, and localize the corrosion progression in plate-like structures. The ultimate objective of this research ...

Diminishing surface wettability is an effective method to improve corrosion resistance of aluminum. Various techniques for preparing hydrophobic surface have been reported, most of which use organic coating as the final step. The key point to diminish surface wettability is to form a fine regular surface structure, and the porous type anodic oxide film (PAOF) has nano-pore structure, therefore ...