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The purpose of this paper was to prepare and evaluate a nanosized mixed calcium iron oxide as a high heat-resistant pigment. Heat-resistant pigments can be defined as chemical substances that impart color to a substrate or binder and retain their color and finish at elevated temperatures. Mixed metal oxides have been widely used as pigments in coating formulations.

This work presents synthesis of nanosized calcium iron oxide as an inorganic pigment by using simple synthesis technique, namely, solid-state calcination method, to study its heat and corrosion resistance. The prepared pigment was characterized by using X-ray diffraction, infrared spectroscopy, scanning electron microscopy and inductive coupling plasma. It was incorporated into paint formulations, and the heat, corrosion and mechanical resistance of dry paint film was evaluated.

In this work, the prepared calcium iron oxide pigment showed excellent heat and corrosion resistance.

Heat-resistant coatings are required for industrial applications, mainly for reactors, exhaust pipes, space craft, stacks and similar equipments that are permanently and occasionally exposed to elevated temperatures. It was previously quite difficult to formulate heat-resistant organic coatings because of binder deficiencies; new vehicles for such applications are now available. Thus, the development of silicon resins has markedly advanced the utility of heat-resistant paints. High-temperature pigments are inorganic chemical compounds that impart and retain their color and finish to a substrate or binder at elevated temperatures.

The nanosized mixed calcium iron oxide could be used as a pigment in paint formulations. It was found that it significantly enhances the heat, corrosion and mechanical resistance. It can also find numerous applications in other paint formulations for surface coating.

The paper shows how the pigment consisting nanosized mixed calcium iron oxide could be used in heat-resistant paint formulations for coating metal surfaces.

This work aimed to prepare black transition metal oxide pigments to be used as solar absorbers in the solar selective and other industrial paints.

Mixed metal oxide CoCuMnO_x spinel pigments were synthesised via the sol‐gel route. These oxides, namely (I‐Co_0.50Cu_0.25Mn_0.25)O_x, (II‐Co_0.25Cu_0.50Mn_0.25)O_x and (III‐Co_0.25Cu_0.25Mn_0.50)O_x, were prepared with different molar ratios and annealed at 600, 800 and 900°C, respectively. The prepared oxides were characterised by infrared spectrometer (IS), differential scanning calorimetry analysis (DSC), X‐ray diffraction (XRD) and transmission electron microscope (TEM).

The prepared pigments have a spinel structure with the composition CoCuMnO_x. All synthesised pigments consisted of nano particles ranged from 10 to 80 nm. The optical properties showed high absorption and moderately low reflectance in the solar wavelength range.

The prepared samples, used in the present work, were synthesized from cobalt sulphate, copper chloride and manganese chloride. The salts were dispersed in polyacrylamide as a precursor.

The prepared samples were thermally stable and had good optical properties. They could be used as absorber materials in the painting of solar collectors.

These thermally stable mixed metal oxides could be used in the painting of solar collectors. The three mixed metal oxides could be used as absorber materials for heating solar collectors due to their high absorption and moderately low reflectance in the solar wavelength range.

The purpose of this paper is to investigate the synthesis of calcium-based group of mixed metal oxide (MMO) pigments. The evaluation of these pigments as heat and corrosion resistant was also explored.

Two simple synthesis techniques, namely, co-precipitation and solid-state calcination method, were used to synthesise nanosized MMO pigments. And then the physico-chemical requirements according to standards for the synthesised pigments are investigated.

The prepared MMO pigments were mainly in the single phase double oxide forms. The prepared oxides exhibited good heat (up to 600°C) and corrosion resistance properties (in 5 per cent NaCl for 500 h).

This paper investigates the physico-chemical properties of synthesised calcium-based group of MMO pigments. And then evaluate it as heat and corrosion resistant paints. The simple techniques used for synthesis of nanosized MMO pigments will significantly improve the research and development of pigments’ structure and performance.

Calcium-based MMO pigments can be used as heat and corrosion resistant pigments. The easy synthesis of the mixed oxide pigments will open the door for further vital special industrial uses and applications.

Low cost, simple techniques and using naturally abundant material can be used for mass production of some other low-cost nanosized materials.

A mixed metal oxide-based spinel ceramic pigment has been successfully synthesized incorporating inorganic, high-temperature stable furnace cement as an inbuilt binder. Step by step synthesis was done for the spinel and cement mix formulations.

The pigment mix was synthesized by a solid-solid method where the inorganic binder was incorporated in the mix. The results suggested that CoCuMn-based spinel ceramic pigment with cement mix could be obtained at an annealing temperature of 1,100ºC for 1 h and the size, morphology and crystallinity of spinel mix were greatly influenced by the calcination temperature.

The pigment mix synthesized was applied as a coating to different substrates such as aluminum, glass and Mild steel. The results revealed that spectral selectivity of TSSS paint coatings based on the CoMnCu spinel ceramic mix was much better than that of solvent-based coatings for high-temperature applications. The presence of cement as an inorganic binder makes the functioning and application of paint easy as it becomes that of a waterborne type.

Ease of application, stability at high temperatures, best absorptivity at the solar selective spectrum and excellent adhesion properties for the selected surface are the key features of the designed pigment system. The applied pigment mix was studied as a coating to get the results for solar selective system.

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.

The purpose of this paper is to search for toxic anticorrosive pigments’ substitute in protective coatings is one of the important tasks that the specialists in the field of steel corrosion face.

One of the ways to solve the problem of metal corrosion is to use complex oxides as pigments, which are characterized as low-toxic compounds and possess the ability to inhibit corrosion.

In the production of ferrites, it is possible to use production waste as raw material, and that makes it possible to reduce the price of the resulting product and solve environmental problems simultaneously.

Permanent growth of world production is accompanied by the increasing environment corrosiveness, associated with the intensification of air, water basin and soil pollution by industrial waste. This, as well as the continuously increasing operated metal stock, has recently made the tendency of metals’ total loss from corrosion steadily increasing. All of this points to the importance of studying corrosion processes and the systematic and effective fight against metal corrosion.

This study aims to study the effect of the reinforcement of mixed CeO₂-ZrO₂ nanoparticles in the polyurethane (PU) for protection properties of steel structures.

Electrochemical techniques were used to study the anticorrosion properties of the generated PU/CeO₂-ZrO₂ nanocomposite coated steel. Dynamic mechanical testing was done to investigate the mechanical properties.

In natural seawater, Electrochemical impedance spectroscopy experiments indicated outstanding protective behaviour for the PU/CeO₂-ZrO₂-coated steel. The coating resistance of the PU/CeO₂-ZrO₂ nanocomposite coating was found to be roughly 30% greater than that of the PU coating. Scanning electron microscopy with energy dispersive X-ray spectroscopy and X-ray diffraction analyses of the coated steel surface revealed that the CeO₂-ZrO₂ was accumulated at the corrosion products, preventing the corrosion. Dynamic mechanical analysis revealed that when the nanoparticle concentration was 3 Wt.%, the PU/CeO₂-ZrO₂ nanocomposite coating had improved dynamic mechanical parameters.

The coating resistance of the PU/CeO₂-ZrO₂ nanocomposite was determined to be 2999.17 kΩ.cm². The perceived current by scanning electrochemical microscopy analysis across the PU/CeO₂-ZrO₂ coating was 1.7 nA. The PU/CeO₂-ZrO₂ nanocomposite had a good hydrophobic behaviour (WCA: 101o). The newly synthesised PU/CeO₂-ZrO₂ composite offered great barrier and mechanical properties, preventing material degradation and increase the lifespan of the coated steel. Hence, this form of coating could be used as a viable coating material for industrial purposes.

The purpose of this paper is to present the results of studies on the reaction of metal oxides such as Cr₂O₃ and Al₂O₃ with Na₂SO₄ in flowing SO₂ (g) at 1,100 and 1,200 K.

The oxides chosen for the studies were initial scaling products during the oxidation of industrial alloys and invariably are involved in hot‐corrosion reactions in the presence of molten salts. The thermo‐gravimetric studies for the system were carried out as a function of Na₂SO₄ in the mixture. The different constituents in the reaction products were identified by XRD analysis and morphologies of the reaction products were discussed on the basis of optical metallography and scanning electron microscopic studies. The pH and conductivity of the aqueous solutions of reaction products were measured and an attempt made to functionalize these parameters with Na₂SO₄ concentration in the mixture. Quantitative estimation of the soluble metal was carried out using an atomic absorption spectrophotometer. The formation of products was investigated by thermodynamic computation of free energies of the reactions and the study of relevant phase stability diagrams.

Looking at the complex nature of the reactions, it is difficult to generalize the conductance studies, as many complex species are liable to hydrolyze in the aqueous solution. However, the break in few curves at certain mole fraction of Na₂SO₄ indicates the presence of soluble complex species.

The paper provides information regarding the reaction between a pertinent oxide and Na₂SO₄ and proper identification of reaction products, useful for understanding the occurrence and importance of fluxing reactions and in the interpretation of hot corrosion mechanism and the development of new protective materials.

The spectrally selective solar absorption paint is prepared from spinel-based mixed metal oxides with inorganic binder as a key component. Inorganic binder (furnace cement) is blended with mixed metal oxide pigment during synthesis. High temperature stability upto 1,100ºC is achieved by the use of this modified coating system. The purpose of this paper is to work on solar selective coating synthesis, and application of a coating as a water-borne paint is the additive key feature that helps in reduction of solvent use.

The paint was formulated using water-based system, and the main component of colorant was made by mixed metal oxide–based spinel pigment and highly temperature stable inorganic binder.

The paint formed shows excellent absorptive power with low emittance even at high temperature. Optical and thermal properties were determined along with adhesion, abrasion and other properties. The solar absorptance for these samples were as = 0.93–0.95 with corresponding thermal emittance of eT = 0.096 (at room temperature) and 0.2–0.22 (at elevated temperature 100°C).

The paint formed shows excellent absorptive power with low emittance even at high temperature. The paint can be applied in solar absorptive tower system. The obtained results indicated excellent thermal stability of prepared paint coatings. As inorganic binder was used, the paint has reduction in solvent use, and being water as a base, it is environment friendly, easy to apply and durable at high temperatures, as the binder itself is stable up to 1,500ºC.

The spinel‐type pigments of a general formula corresponding to AB₂O₄ containing as A the Mg²⁺ or Zn²⁺ ions and as B the Fe³⁺ or Al³⁺ ions or combinations of both the A and B were prepared and investigated with respect to their anticorrosive action as pigments in organic coatings. For the same purposes, comparative pigments, known for their efficiency as the metal‐corrosion inhibiting ingredients in similar formulations, were used. Further evaluation was carried out on the properties of condensed phosphates as anticorrosion pigments. The results obtained showed the high anticorrosion action of the spinel‐type pigments.