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The purpose of this study was to investigate the performances of two inhibitors in controlling corrosion of steel products in industrial and marine atmosphere.

Corrosion rates were determined by weight loss measurements. At certain periods of atmospheric exposure, the (disc shape) specimens were retrieved and studied by scanning electron microscopy and energy-dispersive spectrometry surface analysis techniques.

Both inhibitors were effective against corrosion of steel in the early stages of the atmospheric exposure (for about two months). With further exposure to the atmosphere, their inhibition effectiveness deteriorated and was totally lost within four months. Analysis of the specimens before exposure showed that the inhibitor film was thin for both treatments, and the unexposed treated surface for both inhibitors appeared similar to the untreated unexposed specimen surface. Characterization of the specimens at different exposure periods showed fewer corrosion blisters on dicyclohexylamine nitrite- and sodium benzoate-treated surfaces than on untreated specimens.

The objective of this study was to characterize the surfaces of the steel products produced locally during their exposure to the industrial and marine atmosphere of the Arabian Gulf region after being treated by sodium benzoate and dicyclohexylamine nitrite in controlling the corrosion of local mild steel products. According to the literature review, this study is original and will add value to the studies of inhibition of steel corrosion under similar environments.

The purpose of this study was to determine the atmospheric corrosion behavior of aluminium (Al) exposed to the industrial and coastal environments of northeastern Arabian Peninsula for a period of 15 months.

The samples were exposed under atmospheric, underground and splatter zone conditions at the coastal region. Soil, groundwater, seawater and air particulate samples obtained from the exposure site were analyzed. Secondary electron microscopy was used to identify and study the microstructural features of the corrosion products formed at the surface of the test coupons. The corrosion rates of the samples were determined by the weight loss method.

The results showed that Al exhibited a moderate corrosion rate despite high degree of variation in temperature and humidity and large concentrations of chloride and sulfate in this region. Splatter zone environment was the most corrosive because of high chloride concentrations in seawater and the alternating wetting–drying cycles.

In this paper, corrosion of Al was evaluated in atmospheric, soil and splatter zone conditions along the northeastern coast of Arabian Peninsula and was also compared with the results of the test reported for other international locations.

The purpose of this paper was to determine the mode and cause of failure of polyester-coated galvanized corrugated steel sheets that exhibited degradation of the coating after seven months into service.

Visual inspection and light microscopy revealed the extent of damage exhibited by the panels. Standard metallographic techniques were used to prepare samples obtained from both unused and failed sections. Light microscopy, scanning electron microscopy combined with energy dispersive x-ray spectroscopy and x-ray diffraction techniques were used to study the surface morphology, microstructural features, elemental composition and structure of the samples.

The failure occurred in the form of delamination and blistering of coated layer. Presence of solar radiation, humidity and water retention resulted in loss of adhesion, leading to coating delamination and flaking especially at the top surface. The coating at the bottom surface of the panels showed evidence of blistering caused by water vapor differential that existed between the environment and the coating because of prolonged (four months) wet conditions that existed at the manufacturer’s site during storage.

It is recommended that the coated panels are stored in covered area where direct exposure to atmospheric conditions can be prevented. If open storage is unavoidable, then the use of tarpaulin or plastic sheet as covering and vapor-phase inhibitors was recommended.

This paper provides an account of failure analysis of metal sheet panels. It identifies the mode and cause of failure and also provides recommendations to avoid such occurrences in the future. The information contained in this paper is useful for plant engineers and project managers working in the metal sheet industry.

The purpose of this paper is to determine the long‐term corrosion behavior of cast iron coupons in the Jubail Industrial City (JIC), Saudi Arabia.

The samples were exposed under atmospheric, underground, and splash zone conditions, at Khaleej Mardumah Test Station (KMTS) in Jubail. Soil, groundwater, seawater and air particulate samples were collected at the exposure sites and were analyzed. Secondary electron microscopy (SEM), X‐ray diffraction (XRD) and X‐ray fluorescence (XRF) were used to examine the surface morphology of the test coupons and identify the corrosion products developed on the surface of the metals. The corrosion rates of the coupons were determined by weight loss method.

The results showed that the atmosphere, underground and splash zone conditions all were very corrosive to cast iron, due to temperature and humidity variations as well as the high chloride and sulfate concentrations in the region. The splash zone was the most corrosive regime of the three test zones. The main corrosive ions in the environments were identified as chloride and sulfate. The maximum chloride and sulfate concentrations were measured to be 8.94 and 49.65 μg/m³ in atmosphere, 8,040 and 1,410 ppm in soil, and 29,500 and 5,770 mg/l in seawater, respectively. The corrosion rates of cast irons were found to be 343‐536 μm/y in splash zone, 90‐214 μm/y in underground, and 22‐27 μm/y in atmosphere. Compared to other parts of the world, the soil, marine and atmospheric environments at the selected test site are very corrosive.

In this paper, corrosion of cast iron is presented in atmospheric, soil and splash zone conditions along the eastern coast of the Arabian Gulf.

The purpose of this paper is to study the inhibition of carbon steel corrosion under wet/dry conditions using electrochemical techniques.

Sodium dihydrogen orthophosphate, dicyclohexylamine nitrite and sodium benzoate were used as inhibitors in the investigation. Plain carbon steel specimens were treated with three different inhibitors for a set period of time. One group of the specimens was subjected to 60 wet/dry cycles whilst a second group was kept continuously immersed in distilled water during the same period. The corrosion rates of the specimens were determined by electrochemical methods at several intervals during corrosion.

The three inhibitors showed good performance during the whole 60 days of wet/dry cycling. Sodium dihydrogen orthophosphate was the best of the three, giving the lowest corrosion rates. However, during full immersion tests in distilled water, specimens that had been treated with dicyclohexylamine nitrite and sodium benzoate performed better than did those treated with sodium dihydrogen orthophosphate. Moreover, the corrosion rates were significantly higher in the case of wet/dry cycling due to differential aeration created through partial immersion, which was a consequence of the wet and dry cycling process.

This study showed the beneficial effect of inhibitors in slowing down the corrosion of steel. Furthermore, wet/dry cycling of steel samples in the laboratory produced corrosion rates that were comparable to those measured under actual outdoor conditions.

The purpose of this investigation was to evaluate the performance of high velocity oxy fuel (HVOF) coated SS-310 samples in a carburizing environment.

The carburization behavior of metallic coatings with three different compositions was studied under isothermal carburizing exposure conditions at 900°C for 125 hours. The coatings were deposited on SS 310 substrates using the HVOF technique. The ASTM Standard method was used to evaluate coating adhesion. Scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, X-ray diffraction and weight gain were used to evaluate the surface morphology, microchemical composition, phase constitution and degree of environmental protection imparted by the coatings.

The experimental results indicate that Ni-rich coating offered better protection to SS 310 alloy compared to Co-rich coatings in carburizing environments. This was thought to be due to the formation of a continuous protective layer of Cr₂O₃ on the Ni-rich coating surface.

The study has direct practical relevance to the petrochemical industry, particularly for refinery applications. In refinery service, SS310 is used in header damper plates. The useful service life of such header plates can be extended by the use of high temperature corrosion resistant metallic coatings. The present investigation highlighted the protection offered by Ni-based HVOF coated SS-310 samples in carburizing environment.