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Purpose - The purpose of this paper is to verify the capability of pigmented coatings to mitigate the effects of thermal sensitisation of 430 stainless steel. Design/methodology/approach - 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. Findings - 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. Practical implications - 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. Originality/value - 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. Anglická klíčová slova: stainless steel; coatings; pigments; corrosion; destabilisation; welding; corrosion resistant ferritic steels; anticorrosive pigment; zinc; organic coating Práce se zabývá možnostmi zvýšení korozní odolnosti svařovaných korozivzdorných ocelí. V místě sváru a jeho okolí dochází ke zcitlivění materiálu na korozní působení. V práci jsou testovány možnosti zvýšení korozní odolnosti na těchto senzibilizovaných materiálech po povlakování pigmenovanými nátěry s různým složením.

The properties of calcined kaolins in paints were identified in relation to their pigment volume concentration (PVC). The study involved three kinds of kaolin exhibiting different development of the lamellar structure of primary particles as well as different distribution of particle size. Kaolins also displayed varying contents of a glassy phase – mullite and quartz. Prepared model paints were formulated with the increasing content of kaolins, with PVC ranging from 5 to 40% up to a maximum critical pigment concentration (CPVC), i.e. up to a point where PVC = CPVC. The properties of paints were tested by means of laboratory corrosion tests in the environments of neutral salt mist and of condensed humidity. It was the aim of the study to identify the effect of kaolin's PVC on the mechanical and corrosion resistance of coatings based on water-borne epoxy resin.

PurposeThe purpose of this paper is to clarify the destabilisation mechanism that occurs with two types of ferritic corrosion‐resistant steel during the welding cycle.Design/methodology/approachA 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.FindingsA 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.Practical implicationsIdentification 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.Originality/valueThe 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.

Driers are added to air drying paints to accelerate the hardening of spread coating. For decades cobalt octoate has been the most widely used drier because of its good performance at ambient temperature. Recently, several reports describing possible carcinogenity and genotoxicity of cobalt and cobalt salts, such as cobalt sulfate in aerosols, have appeared. It is necessary to reduce the amount of cobalt compounds in coatings industry. Present study deals with the possibility of using ferrocene and its derivatives as driers for air drying coatings. We concentrated particularly on the synergic effect between these metallocene complexes and the cobalt drier. In the first step the kinetics of autooxidation by FTIR spectroscopy in model systems was investigated. Then the metallocene complexes were applied together with cobalt drier to alkyd resin, where their influence on hardness of spread coatings was examined.

We describe preparation and characterization of multilayer planar systems based on alternating chalcogenide As–Se and polymer polyamide-imide (PAI) or polyvinyl-butyral (PVB) thin films. We deposited films of thermally evaporated As 33 Se 67 chalcogenide glass periodically alternating with PAI or PVB films. Fifteen layers of As – Se + PAI system and 17 layers of As – Se + PVB system were deposited. The film thicknesses were approximately 100 nm for all of the film types. Polymer film thicknesses were calculated from profilometric measurements performed by an atomic force microscopy. Optical properties of prepared multilayers and also As–Se, PAI and PVB single layers were established using UV–vis–NIR and ellipsometric spectroscopies. Both, As – Se + PAI and As – Se + PVB multilayer systems, exhibited the reflection (stop) bands centered near 830 nm. The bandwidth of reflection band of As – Se + PAI multilayer was 90 nm while bandwidth of As – Se + PVB system increased to 150 nm because PVB films had about 0.2 lower refractive index. A new possibility for the application of chalcogenide thin films appeared as high refractive index materials suitable for fabrication of optical elements (reflectors) for near-infrared region. Changing the films composition and thickness, multilayer systems with tailored position of stop band could be designed and prepared.

The objective of this work was to identify the anticorrosive efficiency of synthesised, core pigments. Epoxy ester based coatings containing the synthesised pigments were formulated. To test the anticorrosion properties of the coatings, accelerated corrosion tests were carried out in the environment of condensed water, of NaCl mist, and of condensing water and SO2. The synthesised core shell pigments have good anticorrosion efficiency in an epoxy ester coating. The synthesised pigments do not contain any environmentally harmful substances.

The present paper shows that soluble alkaline silicates, for example sodium silicate, act as flash rusting inhibitors, while aqueous dispersion binders were used in primer paints. Sodium silicate, potassium silicate and lithium silicate were studied for this purpose. Their inhibiting properties were described with the aid of a scanning method, determination of metal weight loss and SEM. Sodium silicate was identified as a very good flash rusting inhibitor for applications in styrene acrylate water borne paints.

The purpose of this technical guide (hereafter referred to as the Species Protocol Technical Guide) is to provide guidelines for developing inventory and monitoring (I&M) protocols for wildlife, fish, and rare plants (WFRP) using the U.S. Department of Agriculture (USDA) Forest Service technical guide format.

Bounding coordinates: West Bounding Coordinate: -124.961735; East Bounding Coordinate: -116.415546; North Bounding Coordinate: 46.344729; South Bounding Coordinate: 41.914842.