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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.

The purpose of this paper is to investigate the effect of a sealing protective treatment on the water absorption and mechanical properties of acrylonitrile butadiene styrene (ABS)-printed parts by fused deposition modelling. Protective products include aqueous acetone solutions with different concentrations, polyurethane wood sealer and aqueous acrylic-based varnish.

Open porosity was estimated by the absorption coefficient and the total amount of water retained, obtained from water absorption tests. Mechanical characterization was performed by compressive and tensile tests. Different specimens with different build directions and raster angles were used.

The treatments with acetone solutions were not effective in reducing the porosity of ABS parts, as the amount of acetone that reduces effectively the porosity will also affect the sample dimensional stability. The polyurethane treatment was found to reduce the absorption coefficient, but the maximum water content and the open porosity remain almost unchanged in comparison with the ones obtained for untreated specimens. The treatment with an acrylic-based varnish was found to preserve the dimensional stability of the specimens, to reduce the open porosity and to maintain the compression and tension properties of the specimens in different build directions and raster angles.

Surface modification for water tight applications of ABS 3D printing parts enables new designs where both sealing and the preservation of mechanical properties are important. As per the knowledge of the authors, the water absorption and the mechanical behaviour of ABS 3D printed parts, before and after treatment, were not previously investigated.

Earliest localism was sited on a tree or hill or ford, crossroads or whenceways, where people assembled to talk, (Sax. witan), or trade, (Sax. staple), in eggs, fowl, fish or faggots. From such primitive beginnings many a great city has grown. Settlements and society brought changes; appointed headmen and officials, a cloak of legality, uplifted hands holding “men to witness”. Institutions tend to decay and many of these early forms passed away, but not the principle vital to the system. The parish an ecclesiastical institution, had no place until Saxons, originally heathens, became Christians and time came when Church, cottage and inn filled the lives of men, a state of localism in affairs which endured for centuries. The feudal system decayed and the vestry became the seat of local government. The novels of Thomas Hardy—and English literature boasts of no finer descriptions of life as it once was—depict this authority and the awe in which his smocked countrymen stood of “the vicar in his vestry”. The plague freed serfs and bondsmen, but events, such as the Poor Law of 1601, if anything, revived the parish as the organ of local government, but gradually secular and ecclesiastical aspects were divided and the great population explosion of the eighteenth century created necessity for subdivision of areas, which continued to serve the principle of localism however. The ballot box completed the eclipse of Church; it changed concepts of localism but not its importance in government.

Corrosion in metals can be likened to cancer in man. It is insidious. In its early stages remedial action can be taken, but if it progresses too far there is no cure — only destruction. Corrosion results from the tendency for a metal to return to its natural state, similar to that of the metallic ore from which it was obtained.

STIMULATING the interest of the employee in his job has become one of the most challenging problems facing management today. Daily repetition of tasks seemingly unrelated to the end product can very quickly cause boredom and fatigue, reducing individual efficiency and lowering productivity.

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.

A lattice‐work structure made of galvanized steel angles bolted together has been in use for some time as a support tower for an overhead conveyor system, it has been noticed that the steelwork is now badly discoloured by corrosion product and it has been decided to take steps to give the structure further anti‐corrosion treatment. The tower cannot be dismantled.

Because it is cheap, plentiful, strong, and reasonably easy to work, sheet steel continues to be the favourite material for the production of basic structures—usually integral body‐chassis fabrications—in the motor industry. Moreover, because conventional rust‐inhibition, paint‐preparation and paint‐coating systems and materials are now cheap and reliable, once the relatively costly equipment is installed, these are still the accepted processes for protection against corrosion, as well as for enhancing the appearance of the product.

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.