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This study aims to investigate a chromium-free sealing treatment process to replace the chromate sealing process in response to the environmental hazards caused by chromate in the Phosphate chemical conversion (PCC) coating post-treatment sealing process.

In this paper, chromium-free sealing technology was used to post-treat PCC coatings. Scanning electron microscopy was used to investigate the structure of the surface of the PCC coatings after the sealing treatment, and the corrosion resistance, hydrophobicity and bonding were tested using an electrochemical workstation, a copper sulfate spot-drop test, a lacquer bonding test, a contact angle meter and a neutral salt spray test.

Chromium-free closure makes the grain distribution on the surface of the PCC coating more uniform and dense, and forms an organic film on the surface of the coating, which significantly improves the corrosion resistance and hydrophobicity of the PCC coating, does not affect the coating film bonding force and has similar performance with potassium dichromate solution.

The results show that the corrosion resistance of PCC coatings after chromium-free sealing treatment is improved, and chromium-free sealing has the potential to replace chromium sealing.

The purpose of the paper is to show the corrosion effect of benzotriazole in comparison with iron phosphate (PFe) coating as a sealer for the PFe layer in carbon steel paint pre-treatment and to show its ecological advantages as a more environment-friendly inhibiting compound than PFe.

Samples of carbon steel (SAE 1010) were phosphated in two baths, one containing iron PFe and PFe and BTAH (PFe + BTAH). Anodic potentiostatic polarization curves and electrochemical impedance spectroscopy were used to evaluate the corrosion resistance of phosphated carbon steel in 0.1 molL−1 H₂SO₄, 0.5 molL−1 NaCl and 0.1 molL−1 NaOH. The phosphate layers obtained were analyzed by infrared spectroscopy. Surface observation by scanning electron microscopy (SEM) showed that the PFe and PFe + BTAH layers are deposited as crystals with granular morphology. The electrochemical results showed that the PFe + BTAH coating was more effective in corrosion protection of the carbon steel.

This paper presents the application of benzotriazole as post-treatment of PFe-coated carbon steel. The results show that benzotriazole improves the phosphate layer properties. The SEM micrographs showed that the layer formed in PFe and PFe + BTAH baths consists of grain-like crystals, and infrared results revealed the BTAH presence in PFe phosphate. The corrosion resistance results showed higher efficiency associated to the PFe + BTAH phosphate layer relative to that of PFe. From the present study, results can be concluded that BTAH can be used as a post-treatment for PFe phosphate coating.

This paper deals with the corrosion resistance and surface carbon steel characterization of a new sealer for PFe coating, which has been prepared for this study and was never tested previously. These are candidate materials for substitution of chromium sealer. The BTAH sealer presents environmental and corrosion resistance advantages when compared with the post-treatment based on chrome. Although BTAH improves PFe layers’ properties, it is the worst phosphate coating. This manuscript has never been previously submitted and deals with original results.

Potassium silicate sealer was applied on solvent-cleaned, acid-pickled, dacromet-coated steel to improve its corrosion resistance. The purpose of this paper is to study the corrosion behavior of dacromet-coated steel.

Potassium silicate sealer was applied on solvent-cleaned, acid-pickled, dacromet-coated steel to improve its corrosion resistance. Electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and salt spray were carried out. SEM was used to study the morphological appearance of the surface.

The EIS behavior indicated that solvent-cleaned dacromet-coated steel sealed with potassium silicate showed that the corrosion current density was 2.664E − 5 A.cm² which was reduced to 8.752E − 6 A.cm² and the corrosion rate, which was 2.264E − 2 mm.year⁻¹, was reduced to 7.438E − 3 mm.year⁻¹ in NaCl 3.5 wt.per cent. EIS was used in NaCl 3.5 wt.%, and the Bode plot characteristics showed that the corrosion protection of solvent-cleaned, dacromet-coated steel was enhanced when sealed with potassium silicate. The EDS results of salt-sprayed, solvent-cleaned samples after 10 days indicated that the main corrosion products are composed of SiO₂, ZnO and Al₂O₃.

The detection of Li element in EDS was not possible because of the device limitation.

The current paper provides new information about the sealing properties of potassium silicate and its effects on the corrosion resistance of dacromet coating, which is widely used in many industries such as the automobile industry.

The object of this article is to disclose the results obtained from a programme of work studying the use of zinc‐rich paints as primers for painting systems to be exposed to marine immersion. This programme was commenced early in 1963 with a view to deriving information on the way these systems functioned and hence to establish a code of practice which would enable personnel responsible for the protection of marine structures to obtain the best results with systems based on these primers.

Drying paint, varnish or lacquer coatings on any substrate is a study in inefficiency if we try to relate the energy input to the energy which actually dries and converts the surface coating.

To give a brief review discussing all areas of technology is an impossible task — however, many engineers, consultants etc., have to decide from a mass of literature what system to use for a particular project. The author's company give a free world wide service in technical advice in the following areas — marine, tank lining, pipe coating, offshore rigs and structures, jetties, dock gates, bridges, chemical plants and all other structures exposed to severe conditions. The following general comments should provide a basis for consideration.

Macpherson Paints has introduced a problem‐solving Stain Sealer to their general products range to meet the growing demand for water‐based paints.

A range of tape dispensers has been introduced by the Minnesota Mining & Manufacturing Co. Ltd. Three machines recently shown for the first time are a continuous can sealer, a flat surface applicator and a combination bundler.

READ a current CEGB advertisement and you will no longer wonder why your electricity charges are being generated sky high. “Senior Technical Editor up to £6,630 p.a.” it reads—wow. First of all let's take a look at current job descriptions at around £6,000 p.a. A glance at “The Daily Telegraph” reveals the following: “Senior Civil Engineer £5,000—£6,500”; “Chief Compressor Designer £4,000”; “General Manager £6,000”; “Works Director £5,000”; “Quality Assurance Manager £5,000”—and all these— and more—are from advertisements of substantial firms in various engineering fields.

Epoxy‐pitch iron ore sealer. Secomastic Ltd. have introduced Micanox EKV, a two‐part epoxy‐pitch sealer coating which is reinforced with micaceous iron ore. It's properties include outstanding resistance to abrasion and to the long‐term effects of immersion in salt water, fresh water, alkalis and aliphatic hydrocarbons. After extensive practical trials, including tests on ocean‐going vessels extending over 3 years, the material showed no sign of breakdown or deterioration.