Corrosion inhibition of ethanol extract of Moringa oleifera leaves on aluminium in 1m sulphuric acid solution

The aim of this research is to use the wet loss method to determine how well Moringa oleifera in H2SO4 inhibits aluminum corrosion. Weight loss was measured before and after corrosion on aluminum coupons with a thickness of 0.15cm, a width of 3cm, and a length of 4cm, all of which were 98 percent pure. Increases in inhibitor concentrations improve inhibition effectiveness, which ranges from 35.29 % to 47.06 % to 64.71 percent to a maximum of 82.35 %, but decreases as temperature and immersion time rise. The inhibition efficiency of the formulation consisting of 1M H2SO4 medium and 0.4g/L inhibition is 82.35 %. This means that the inhibitor is well-adsorbed on the surface of the aluminum metal, resulting in a significant reduction in corrosion rate. As a result, further research into corrosion inhibition should be done with this type of plant. The Langmuir adsorption isotherm (where Gads(kj/mol) is found to be -13.694 and Kads is 13.53) was followed in the adsorption of inhibitor molecules on Aluminum sheet surface. The absorption peaks corresponding to the functional groups – C=O, -C=N, C-OH, and C=C were found in the infrared spectrograph of the leaf extracts. These functional groups may have interacted with the aluminum sheet's surface, preventing oxidation. Organic compounds in the leaf extracts, such as alkaloids, saponins, tannins, and phenolics, were thought to be the source of these functional classes. Green extracts of M. oleifera are recommended for use as corrosion inhibitors against other inorganic compounds. It has a higher inhibitory performance, is readily available, biodegradable, less expensive, and environmentally friendly.

Comparative Study of Chloride and Fluoride Induced Aluminum Pad Corrosion in Wire-Bonded Device Packaging Assembly

The introduction of copper as wire bonding material brings about a new challenge of aluminum bond pad bimetallic corrosion at the copper/aluminum galvanic interface. Aluminum is well known to undergo pitting corrosion under halide-contaminated environments, even in slightly acidic conditions. This paper aims to study the corrosion morphology and progression of aluminum influenced by different halide contaminations in the presence and absence of galvanic contact with copper. We used a new corrosion characterization platform of the micropattern corrosion screening to simulate the copper wire bonding on the aluminum bond pad. The corrosion screening data and subsequent SEM–EDX analyses showed a striking difference in morphology and progression between chloride-induced and fluoride-induced aluminum corrosion. The corrosion products formed play a vital role in the resulting morphology and in sustaining further aluminum corrosion.

Failure Analysis of an Aluminum Earphone Connector due to Corrosion

Earphones are often exported to foreign countries by sea as consumer goods. In view of the humid marine environment, the earphone packaging box is often placed with anti-mold chips to prevent mold, while the volatilization of the anti-mold chips will also cause corrosion problems. In this study, a large number of aluminum earphone connectors were corroded in the process of ocean transportation, and the corrosion products were located in the left earphone connector close to the anti-mold chips. It’s determined that sulfate and nitrate ions lead to the corrosion of the aluminum connectors, and these are the volatilization products of the anti-mold chips. This conclusion was further confirmed by the simulation test, which was carried out on the anti-mold chips and aluminum connectors at 85 °C, 85% RH humidity for 72 h. The aluminum connectors were obviously corroded, and the morphology and composition of the corrosion products were the same as those on the actual earphones. The corrosion was successfully prevented by a PTFE coating on the surface of aluminum connectors. Keywords: Earphones; Anti-mold chip; Aluminum; Corrosion; PTFE coating