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The aim of the work is to develop an anticorrosion pigment based on an oxide mixture with lamellar particles. The pigments are prepared from lamellar zinc, zinc oxide and magnetite by calcination. An alkaline earth carbonate is added when embedding a third cation in the lattice of the ferrite that forms the envelope of the lamellar zinc. The properties of the pigments are tested both in the powdered state and when embedded in an epoxy-ester system using different pigment volume concentrations (PVC).

The properties of paints containing synthesised oxide mixture-based pigments at various volume concentrations and with the Q factor – Q = PVC/CPVC = 0.65 – were examined (where CPVC is critical pigment volume concentration). A series of isometric ferrite pigments were also synthesised for a comparison. Paints of both types with PVC = 10, 15 and 20 per cent were formulated. Steel panels coated with the paints were subjected to corrosion and mechanical tests.

The oxide mixtures with lamellar particles were subjected to particle size analysis and found to make up a broad distribution curve. Electron microscopy photographs confirmed that the oxide mixture pigments contained lamellar particles with a surface layer. A high anticorrosion effect was achieved owing to the combination of different oxide types.

The properties of the oxide mixtures with lamellar particles are described. Their particle distribution curves can be obtained by particle size analysis methods with a view to obtaining additional information on the status and properties of the pigment particles that may be useful in the development of better paints/coating materials.

Oxide mixtures with lamellar particles can be used in paints protecting construction steel.

The composition of the prepared oxide mixture-based pigments is novel. Each oxide acts by its own anticorrosion mechanism and the final beneficial effect is due to their concerted action.

Studies the spinel pigments containing Zn, Ca, and Mg cations from the point of view of reactivity with corrosive substances of acidic nature, which diffuse through the coating at activated corrosion. Proposes the mechanisms of anticorrosive activities of these pigments in an epoxy resin based binder, showing a high chemical stability. A microscopy method was used for following the diffusion of corrosive acidic substances through the film.

This paper aims to synthesise anticorrosion pigments containing molybdenum for paints intended for corrosion protection of metals.

The anticorrosion pigments were prepared by high-temperature solid-state synthesis from the appropriate oxides, carbonates and calcium metasilicate. Stoichiometric molybdates and core-shell molybdates with a non-isometric particle shape containing Ca, Sr, Zn, Mg and Fe were synthesised. The pigments were examined by X-ray diffraction analysis and scanning electron microscopy. Paints based on an epoxy resin and containing the substances at a pigment volume concentration of 10 volume per cent were prepared. The paints were subjected to physico-mechanical tests and to tests in corrosion atmospheres. The corrosion test results were compared to those of the paint with a commercial pigment, which is used in many industrial applications.

The molybdate structure of each pigment prepared was elucidated. The core-shell molybdates exhibit a non-isometric particle shape. The pigments prepared were found to impart a very good anticorrosion efficiency to the paints. A high anticorrosion efficiency was found with the pigments Fe₂(MoO₄)₃ and Fe₂(MoO₄)₃/CaSiO₃ and with Mg and Zn molybdates.

The pigments can be used for the formulation of paints intended for the corrosion protection of metals. The pigments also improve the paints’ physical properties.

The use of the pigments in anticorrosion paints for the protection of metals is new. The benefits include the use and the procedure of synthesis of the anticorrosion pigments which are free from heavy metals and are acceptable from the aspect of environmental protection. Moreover, the core-shell molybdates, whose high efficiency is comparable to that of the stoichiometric molybdates, have lower molybdenum contents.

The paper deals with using lamellar pigments for anticorrosive barrier coatings. By depositing a ferric oxide layer on a muscovite particle a pigment is obtained, which being applied to coatings improves the mechanical properties thereof, resistance to UV radiation and acts as an anticorrosion barrier. The optimum concentration of lamellar surface‐treated muscovite in the coatings amounts to 20 vol. %.

This paper aims to synthesize anticorrosion pigments containing tungsten for paints intended for corrosion protection of metals.

The anticorrosion pigments were prepared by high-temperature, solid-state synthesis from the respective oxides, carbonates and calcium metasilicate. Stoichiometric tungstates and core-shell tungstates with a nonisometric particle shape containing Ca, Sr, Zn, Mg and Fe were synthesized. The pigments were examined by X-ray diffraction analysis and by scanning electron microscopy. Paints based on an epoxy resin and containing the substances at a pigment volume concentration (PVC) = 10 volume per cent were prepared. The paints were subjected to physico-mechanical tests and to tests in corrosion atmospheres. The corrosion test results were compared to those of the paint with a commercial pigment, which is used in many industrial applications.

The tungstate structure of each pigment was elucidated. The core-shell tungstates exhibit a nonisometric particle shape. The pigments prepared were found to impart a very good anticorrosion efficiency to the paints. A high efficiency was demonstrated for the stoichiometric tungstates containing Fe and Zn and for core-shell tungstates containing Mg and Zn.

The pigments can be used with advantage for the formulation of paints intended for corrosion protection of metals. The pigments also improve the paints’ physical properties.

The use of the pigments in anticorrosion paints for the protection of metals is new. The benefits include the use and the procedure of synthesis of anticorrosion pigments which are free from heavy metals and are acceptable from the environmental protection point of view. Moreover, the core-shell tungstates, whose high efficiency is comparable to that of the stoichiometric tungstates, have lower tungsten content.

Studies the effects of non‐isometric pigments on the anticorrosion properties of coating films. The optimum concentrations for using iron mica, muscovite, and graphite have been determined. The results obtained on using the natural iron mica are compared to those obtained with a synthetic product. As binders for the coatings epoxy resin, polyurethane and alkyd resins were used. The results allow the conclusion that on the pigmentation with iron mica the protection function of top coatings against the corrosive media can be considerably increased.

The purpose of this paper is to synthesize anticorrosion pigments of the perovskite type, YXO₃, where X = Ti, Zr, Mn or Al and Y = Ca, Sr, La or Fe, for coating materials intended for corrosion protection of metals. Also, to synthesize pigments containing hexavalent Mo and W (double perovskites).

The anticorrosion pigments were synthesized from oxides or carbonates by a high-temperature process. The following pigments were synthesized: CaTiO₃, SrTiO₃, CaZrO₃, SrZrO₃, LaTiO₃, LaMnO₃, CaMnO₃, SrMnO₃, LaFe₂O₃, SrFe₂O₃, LaAlO₃, Ca₂ZnWO₆ and Ca₂ZnMoO₆. The pigments were characterized by the physico-chemical properties of the powders, by X-ray diffraction analysis and by scanning electron microscopy. Epoxy-ester coating materials containing the pigments at a volume concentration PVC = 10 per cent were prepared and subjected to tests examining their physico-mechanical properties and tests in simulated corrosion atmospheres.

The perovskite structure was identified in the majority of the pigments. The pigments were found to impart good corrosion inhibiting properties to coating materials. The highest calculated anticorrosion efficiency was found for paints containing CaMnO₃ or SrMnO₃ as the pigments.

The pigments synthesized can be used with advantage in paints intended for corrosion protection of the substrate metals.

The use of the above pigments in anticorrosion coating materials to protect metals is new. Especially beneficial are the uses and procedures for the synthesis of anticorrosion pigments which do not contain heavy metals and are acceptable from the environmental protection aspect.

The purpose of this paper is to verify the capability of pigmented coatings to mitigate the effects of thermal sensitisation of 430 stainless steel.

Experimental weld joints of non‐stabilised ferritic corrosion resistant steel type AISI 430 were prepared. Protective coatings in several variants were applied to a number of weldments, subsequently subject to corrosion tests in SO₂ and NaCl. The anticorrosive efficiency of the coatings was evaluated by means of normative visual assessment and metallographic analysis of the mechanism and depth of corrosion damage.

Anticorrosive efficiency of the tested coatings was experimentally established under conditions where differences were identified in structural changes caused by welding, or resulting from mechanical damage to the coating. Differences in the progress of corrosion damage caused by phase changes in the heat‐affected zone were established.

Tests of anticorrosive efficiency of coatings of selected types provided information about possible reduction in sensitisation of welded non‐stabilised steel. The effect of the investigated processes on degradation of anticorrosive resistance was identified.

A specific effect of phase changes accompanying welding on the corrosion mechanism was described and so were the reasons underlying development of corrosion damage at visually identical character of surface damage.

The purpose of this paper is to clarify the destabilisation mechanism that occurs with two types of ferritic corrosion‐resistant steel during the welding cycle.

A series of experimental weld joints was made to verify the actual response of non‐stabilised corrosion‐resistant steel, and of the same steel that had been stabilised by added titanium. The character and extent of the ensuing structural changes were analysed. The essential characteristics of degradation in the heat‐affected zone are evaluated using optical and scanning electron microscopy; individual phases are identified by means of EDX microanalysis. The underlying mechanism for the loss of stability is induced experimentally in several stages; depending on the thermal doping level and interaction with the environment during the welding process, phases of various types are precipitated. These phases subsequently are studied in connection with the original microstructural characteristics of the steel and the induced grain boundary decohesion of the surface layer. The scope and character of the damage are analysed and the results verified by analysing the actual operating damage to the weldment.

A degradation mechanism of stabilised corrosion‐resistant steel 1.4510 is induced that is associated with destabilisation of titanium phases. The importance is demonstrated of ensuring that a protective atmosphere is maintained during welding, and various phase changes in the surface layers are identified that can delimit the use of appropriate post‐weld passivation procedures.

Identification of the mechanism underlying the damage to the surface layer in welded stabilised ferritic steel will find application in development of welding technology, specifically in designing a technology process and subsequent surface treatment.

The results bring new knowledge of material response of steel 1.4510 under specific material processing conditions; a destabilisation mechanism related to precipitation of several titanium‐containing phases is identified. The result enables the fatigue limit of the welded material as a function of the welding technology employed, which offers increased service life under specific application conditions.

The purpose of this paper is to synthesise X₂TiO₄ spinel‐type anticorrosion pigments and YTiO₃, perovskite‐type anticorrosion pigments, where X = Zn, Mg, Ca, Sr; Y = Ca for metal protective paints.

Anticorrosion pigments were synthesised from oxides or carbonates at high temperature. The following pigments were synthesised: TiO₂ · ZnO, 2TiO₂ · ZnO, TiO₂ · 2ZnO, TiO₂ · MgO, TiO₂ · CaO, TiO₂ · ZnO · MgO, and TiO₂ · ZnO · SrO. The pigments obtained were characterised by means of X‐ray diffraction analysis, measurement of particle sizes and scanning electron microscopy. The anticorrosion pigments synthesised were used to produce epoxy coatings with PVC = 10 per cent for each synthesised pigment. The coatings were tested for physical‐mechanical properties and in corrosion atmospheres. The corrosion test results were compared with those of alumino zinc phosphomolybdate.

A spinel or perovskite structure was found in the pigments synthesised. High anticorrosion efficiency was identified in all the synthesised pigments, the highest efficiency being demonstrated in the TiO₂ · ZnO pigment of spinel structure and in the TiO₂ · CaO pigment of perovskite structure.

The pigments synthesised can be conveniently used to protect metal bases from corrosion.

The use of pigments synthesised in anticorrosion coatings for metal protection presents a new approach. Its benefits are the use and the method of synthesising the anticorrosion pigments that do not contain heavy metals and that are acceptable for the environment.