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For years, coated metal sheets have been used in cookware manufacturing. This paper focuses on employing experimental and numerical analyses to determine the quality and formability of commercially available polytetrafluoroethylene (PTFE)‐coated aluminium sheets. For this purpose, examinations of the coating's microstructure, hardness, and friction coefficient through nano‐indentation and scratch tests, were investigated. Tensile test was performed to obtain some mechanical characteristics of the coated aluminium sheets. Moreover, the forming limit curve for the studied material was established by conducting Nakazima test, covering both negative and positive domains of minor strain. The influence of sheet thickness on formability was investigated since using 2 mm and 1 mm thick sheets in this work. Finally, the limits of deep drawing process using the finite element method with Abaqus software was studied. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aims to develop tetrahedral amorphous carbon nanocomposite layer coated tungsten carbide drill bits for single shot drilling of composite metal stack. Different coatings were tested for hole integrity performance compared to an uncoated tool and the results were validated using process capability six‐pack analysis. The drilling process employed a 4.85 mm twist drill with a feed rate of 0.05 mm/rev and spindle speed of 2600 rev/min. The experimental results indicate that, all the coated tools produce H9 tolerance holes while uncoated tool produced H7 tolerance holes with 18 % to 35 % better results. But statistical results show that all the tools including uncoated tool require improvement to stay within the control limits. The hole circularity error obtained by all the tools were below 24 μm in both the panels and is supported by the statistical results as well. The uncoated tool exhibited 17.91 % better surface roughness in aluminium panel compared to coated tools, while coated tools produced 17.2 % to 22.3 % better surface roughness in composite panel. Statistical results suggested that, improvement is necessary when drilling aluminium panel by all the tools while dopant added coated tools produce better results in composite panel. [ABSTRACT FROM AUTHOR]

Kurzfassung: Aufgrund einer verschärften Einstufung von Titandioxidpulvern als vermutlich krebserregender Gefahrenstoff, ist mit einer eingeschränkten Nutzbarkeit des fotokatalytisch aktiven Stoffes in allen Sektoren zu rechnen. In dieser Arbeit wird daher eine alternative Anwendung von Titandioxid als fotokatalytisch aktive Bauteilbeschichtung in der Form von angeordneten Nanoröhren vorgestellt, da diese aufgrund ihrer Geometrie nicht von der Neuregulierung betroffen sind. Dies wird durch den direkten Transfer einer durch Anodisation hergestellten Nanoröhrenstruktur auf das zementbasierte Bauteil bewerkstelligt. Die fotokatalytischen Eigenschaften bleiben dabei erhalten. Im Rahmen dieser Arbeit werden dazu Titandioxid‐ und dotierte Titandioxidnanoröhren, welche aus einer Titan‐Eisen‐Legierung synthetisiert wurden untersucht. Zunächst werden sowohl der Herstellungsprozess der Nanoröhren als auch deren Nachbehandlung, um einen Transfer auf den Baustoff zu bewerkstelligen, beschrieben. Anschließend wird gezeigt, dass ein Transfer der Nanoröhren auf den Baustoff in der Fertigteilbauweise erfolgen kann. Die Charakterisierung des Verbundwerkstoffes erfolgt anschließend anhand morphologischer und kristallographischer Daten. Die fotokatalytische Aktivität der Nanoröhren wird mittels eines Farbstoff‐Degradations‐Versuches untersucht. [ABSTRACT FROM AUTHOR]

Kurzfassung: Blasenbildung bei Reaktionsharzbeschichtungen auf zementgebundenen Untergründen ist ein seit vielen Jahrzehnten bekanntes und in der Literatur kontrovers diskutiertes Phänomen. Insbesondere nach dem Aushärten der Beschichtung auftretende Blasen können zu umfangreichen Schadensfällen führen, die eine Erneuerung des gesamten Beschichtungssystems nach sich ziehen. Im Beitrag liegt der Fokus auf der Untersuchung von Blasenbildung zwischen Betonuntergrund (Substrat) und Kunstharzbeschichtung aufgrund osmotischer Prozesse in diesem System. Hypothese ist, dass die Wirkung des zementären Werkstoffs als semipermeable Membran im Verbund mit der darüber liegenden Reaktionsharzbeschichtung unter bestimmten Randbedingungen der Zusammensetzung und des Feuchte‐ und Stofftransports zu Schäden führt. Hierzu werden systematische Untersuchungen mit verschiedenen Substratmörteln, die in Zementart, w/z‐Wert, Zusatzstoffen und Gesteinskörnung variieren, durchgeführt. Des Weiteren kommen vier verschiedene Beschichtungssysteme zum Einsatz. Die Verbundprobekörper werden bei verschiedenen (praxisrelevanten) Umgebungsbedingungen gelagert, um ggf. eine Blasenbildung zu forcieren, und auf diese Weise Ursachenklärung zu betreiben. [ABSTRACT FROM AUTHOR]

The primary intent of the proposed research work is to investigate the effectiveness of the titanium aluminium nitride/tungsten carbide‐carbide coated insert during dry turning structural stainless steel. The aim of the study is to simultaneously optimise machining variables like spindle speed, depth of cut and feed for several responses like flank wear, material removal rate and surface roughness. Titanium aluminium nitride/tungsten carbide‐carbide is coated on the surface of carbide tool by cathodic arc evaporation method. The characterization studies have been conducted to ensure the existence of coating material. Micro hardness of coated and pure inserts was tested, which confirms that titanium aluminium nitride/tungsten carbide‐carbide coated insert possesses 17.43 % augmented hardness over pure inserts. The machining was performed by adopting Taguchi experimental design. A multi‐response optimization approach was applied in this study that included ranking methodology based on data development analysis and Taguchi's design. The performance index for multiple responses was measured and mathematically analysed for their effect on processing parameters. The combination of parameter such as spindle speed: 2000 min−1; cutting depth: 0.45 mm and feed rate: 0.16 mm rev−1 was experimental as optimal machining parameters. [ABSTRACT FROM AUTHOR]

Copyright of Gefaesschirurgie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The technical rules for maintenance and the question of scale in the event of "damage/defects" in legacy cases Wiens/Raupach and Helm have studied the technical rules for maintenance of the German Institute for Building Technology (Deutsches Institut für Bautechnik) of 2020 with new contents and constructional framework conditions, including their application [1]. Schießl‐Pecka/Strehlein have described the repair method as specified in the technical rules for maintenance and the relevance of the W (water reduction) repair principle in particular, in combination with hydrophobic treatments, from the planner's perspective [2]. The basis for the scenarios depicted is essentially the application where repairs need to be carried out on an ageing reinforced concrete structure. In addition to this basic case, the situation also arises where there are indications that a reinforced concrete structure that has already been repaired is in need of further repairs, and consequently action is required. A special case is to be added to these legacy cases – which carry the designation "damage" in legacy cases (repair damage) – which is characterised by defects in repairs carried out on a reinforced concrete structure which come to light in an open‐ended warranty period and the customer asserts claims due to material defects (rectification of repair defects in an open‐ended warranty period, repair defects). Legal rules therefore apply in addition to the applicable technical rules. The article concerns itself with the technical and legal questions that arise in this regard, that also touch on the area of application of the technical rules for maintenance and in particular emphasise the significance of the performance description in contract specifications. [ABSTRACT FROM AUTHOR]

Iron alloy based amorphous coating materials have enormous potential in wide range of applications such as petrochemical, aerospace, ocean, and electronic communications due to their better mechanical properties, chemical properties, magnetic properties and tribological properties. The industrial applications of coating are increasing rapidly due to many advancements in the material development and coating deposition techniques. The present paper reviewed the recent progresses in deposition technologies, development of new high order alloys and composite based coating materials. In this regard, change in microstructure, elemental composition, mechanical and tribological properties on performance of iron alloy based coating properties were presented. It can be concluded that the tribological properties of coating is dependent on pre‐coating and post‐coating factors. Pre‐coating factors include coating deposition techniques, coating layer thickness and coating parameters such as spray distance, oxygen flow rate etc. Post‐coating factors include microstructure, hardness, fracture toughness and adhesion strength. Therefore, multi‐criteria decision making techniques can be the best approach to find the optimum formulation of coating materials to achieve desired set of objectives under the conflicting criteria. [ABSTRACT FROM AUTHOR]

In the present study, three different series of iron alloy based coating materials with varying chromium and titanium content (FeMoCSiBCr10, FeMoCSiBCr10Ti10, FeMoCSiBTi10) were deposited on 316L stainless steel using High velocity oxy‐fuel spraying method. The effect of alloying element chromium and titanium on corrosion, mechanical and erosion properties of iron alloy based coating material was evaluated. Corrosion test was performed in the medium of sodium chloride (3.5 wt.%). Mechanical tests were performed in terms of micro‐hardness and fracture toughness. The solid particle erosion test of iron based coating materials was performed according to steady state condition by varying impact speed and impingement angle. The finding of results indicated that in case of 10 wt.% titanium, the micro‐hardness and fracture toughness was increased by 25.6 % and 16 % respectively, whereas in case of 10 wt.% chromium, the micro‐hardness and fracture toughness was increased by 20.6 % and 9.8 % respectively. It can be concluded for the selection of an alloying element in an iron alloy based coating material, titanium should be given preference over chromium to get better mechanical and solid particle erosion properties whereas chromium should be given preference over titanium to get better corrosion properties. [ABSTRACT FROM AUTHOR]

Corrosion behavior of structural carbon steels grade SS400 coated with copper and zinc exposed to soil sample extracted from the central part of Thailand is studied using weight loss analyses and electrochemical methods, including open circuit potential monitoring for 3600 seconds, electrochemical impedance spectroscopic analyses and potentiodynamic polarization measurements. Bare carbon steels are also examined as a reference. Open circuit potential and polarization resistance of all samples are measured on (1, 2, 3, 4, 7, 10, 15, 30, 45, 60, 77 and 91) days of exposure. Corrosion potential is monitored only on the first and last days. After 91 days, corrosion rate in millimeter per year is calculated from weight loss and corrosion product is characterized. Effects of coating material, thickness and process on corrosion resistance of carbon steel subjected to soil environment are reported and discussed. [ABSTRACT FROM AUTHOR]

The present work focuses on the effect of annealing heat treatment on the microstructure, mechanical and erosion properties of iron alloy based coatings with varying chromium content. High velocity oxygen fuel coating method was used to deposit the coating over the substrate material 316 L stainless steel. The study was done in terms of microstructural analysis using x-ray diffractometer, surface and cross-sectional morphology using field emission scanning electron microscope, mechanical and erosion wear analysis. It was found that x-ray diffractometer indicated presence of less amount of titanium dioxide (TiO2) and silicon dioxide (SiO2) after heat treatment. However, the peaks of hardened phase of diironylidenetitanium (Fe2Ti) and iron-chromium (Fe-Cr) was increased. Addition of chromium up to 10 wt. % improved the hardness and adhesion pull of strength by 16 % and 62 % respectively. On the other side heat treatment of iron alloy based coating having 10 wt. % chromium increased the hardness and adhesion pull off strength by 17.3 % and 35 % respectively. The erosion wear rate was also decreased with the annealing process. The study shows that the annealing process increases hardness and adhesion pull off strength but decreases porosity and erosion wear rate. [ABSTRACT FROM AUTHOR]

Copyright of Tribologie und Schmierungstechnik is the property of Narr Francke Attempto Verlag GmbH & Co.KG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Repair of chloride‐contaminated RC‐components by application of a coating – Investigations on the application limits of methods 7.7 and 8.3 The technical rule of the German Institute for Building Technology (Deutsches Institut für Bautechnik – DIBt) "Maintenance of concrete structures" (TR‐IH) introduced in January 2021 enables two methods for the repair of chloride‐contaminated structures by applying a surface protection system with chlorides remaining in the concrete (to a large extend). The repair method 7.7 "Coating of chloride‐containing concrete" may be applied if the reinforced steel is still passive and the chloride load in the concrete cover ensures a distance of the critical chloride content from the reinforced steel of 10 mm. By developing a closed solution of the diffusion‐controlled chloride redistribution after applying the coating even with partially water‐saturated concretes and a parameter study, it could be shown that the maximum remaining chloride content in the concrete cover may be 2.0 wt.‐%/cem. The repair method 8.3 "Increase of electrical resistance by coating", on the other hand, may also be applied with active reinforcement corrosion. Extensive investigations have widely confirmed the application limits mentioned in the TR‐IH and further sharpened them with regard to concrete quality and the type of surface protection system. Finally, the method is only applicable to chloride levels below 1.0 wt.‐%/cem (considering a chloride redistribution) with a low risk. [ABSTRACT FROM AUTHOR]

Copyright of Technisches Messen is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Subsequent mounting of brackets onto coated steel substrates with insufficient adhesion The contribution describes a method for the subsequent mounting of brackets onto coating with insufficient adhesion to steel substrates. The method provides a high mechanical lap‐shear resistance. It also allows an environmental‐friendly, nearly emission‐free local pre‐treatment of coating areas with insufficient adhesion. An integrated mechanized adhesion test enables an objective assessment of the load capacity of coated substrates along with a decision on whether the brackets can be adhered directly onto the existing coating or onto the locally exposed substrate. [ABSTRACT FROM AUTHOR]

Copyright of Tribologie und Schmierungstechnik is the property of Narr Francke Attempto Verlag GmbH & Co.KG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Influence of the Light Reflectance Value on the crack safety of AAC masonry The brightness of a surface affects the thermal loading of a coating on the masonry or insulation layer underneath. First of all, dark surfaces with low Light Reflectance Value (LRV) are strongly heating up under solar radiation. When applied on highly heat insulating substrates like aerated concrete, the emerging heat is insufficiently conducted away. This causes thermal stresses between coating and substrate. For this reason, manufacturers recommend a limitation of the Light Reflectance Value. However, investigations of the Xella Technologie‐ und Forschungsgesellschaft mbH show that even dark coatings with very low LRV are neither damaged by extreme climate conditions nor cause damage on the AAC load‐bearing layer. Consequently, the LRV seems to be unsuitable to serve as reference for limitation of thermal stresses. Therefore, for dark surfaces, manufacturers further recommend the consideration of the Total Solar Reflectance value (TSR). In contrast to the LRV, this value records the whole energy spectrum of the sunlight and, hence, is a pigment‐independent parameter for evaluation of the warming potential of a coating. Limit value observations concerning this parameter are subject of current investigations. [ABSTRACT FROM AUTHOR]

Subsequent mounting of brackets onto coated steel substrates with adhesives The performance of adhesively mounted brackets onto completely coated steel substrates is investigated. The investigated joint connections on polyurethane, polysiloxane and epoxy coatings exhibit a high mechanical stability even after accelerated ageing (salt spray exposure, cyclic temperature variations, high relative humidity). Tensile strength and shear strength criteria for a designed loading capacity of 50 kg are achieved with a factor of > 10. All failure strength values are lower than the adhesion strength of the coatings to the steel. The torsional rigidity of the adhesive joint exceeds the required clamping torque of the bolt. A cyclical lifetime of > 9 ⋅ 106 load cycles is estimated. Effects of cyclic ageing on the creep performance of the adhesive joint are found to be insignificant. The joint connections meet the requirements for a safety factor for the design for marine applications. [ABSTRACT FROM AUTHOR]

This study deals with the concept of increasing energy efficiency by means of decreasing the energetic losses by using advanced composite machine tool components and interfaces characterized by low friction, and high wear resistance. Moreover, this study provides experimental results of damping property measurements and characteristic time domain curves of the fibre, particle, and sandwich composites, underlining the advantages of such composite types in terms of dynamic loading. Furthermore, it provides an analysis on the usage of thin films (coatings) and energy consumption in terms of cutting conditions. The study analyses the cutting tool geometry and shape of cutting edge that positively affect the cutting forces and chip flow direction, and avoid the energy‐intensive restricted cutting effect. Respecting the results of the analyses of mentioned effects contributes to increasing the energy efficiency of the machine tool‐cutting tool‐workpiece system. [ABSTRACT FROM AUTHOR]

Copyright of Tribologie und Schmierungstechnik is the property of Narr Francke Attempto Verlag GmbH & Co.KG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: New research results for the protection of building components under paving The use of permeable paving for parking areas e.g. is now one of the most common variants in single‐storey underground car parks without ground water or the ground floor of parking garages to avoid the relatively expensive to be coated and reinforced concrete floor slabs as a roadway. If a load‐bearing floor slab is not used, the loads are discharged into the ground via single and strip foundation under the paving slab. Accordingly, the entrained meltwater entrained by cars passes through the permeable pavement to the components lying in the ground. In order to ensure the durability of the reinforced concrete components under the pavement surface in the event of exposure to chloride, the planner must take appropriate measures. The studies presented by the University of Applied Sciences Munich on parking garages show that there can be significant chloride contamination both on the rising components and on the foundations. Furthermore, the permeability of paving coverings scatters strongly. The laboratory studies carried out by a DBV‐sponsored research project show that the coating of reinforced concrete components can be damaged by the installation of the plaster pavement. Furthermore, it was found that not all coating systems defined in accordance with RL‐SIB provide a practical outsourcing that sufficiently protects the reinforced concrete components against corrosion. In the laboratory tests, flexible sealing slurries or OS 5b systems – which have been tested for permanently occurring chloride‐containing water – proved to be most suitable and can be recommended. [ABSTRACT FROM AUTHOR]

Abstract: A material consisting of an in‐situ titanium carbide reinforced nickel‐aluminide (Ni3Al) coating and a powder metallurgy master alloy was fabricated by vacuum hot‐pressing sintering technology. A metallurgical bonded, pores‐free interface between composite coating and powder metallurgy master alloy was formed at the sintering temperature of 1050 °C, pressure of 10‐4 Pa and pressing pressure of 40 MPa. The phase, microstructure and wear behavior of composite coating were investigated. The results showed that polygonal titanium carbide particulates with various sizes were homogeneously distributed in nickel‐aluminide matrix. The sintering temperature, pressing pressure and heat from as‐reactions‐formed coating green compact facilitated the pore infiltration with transiently generated liquid phases and ensured the high‐intensity metallurgical bonding between composite coating and powder metallurgy master alloy. Due to the abnormal elevated‐temperature properties of nickel‐aluminide matrix, titanium carbide particulates reinforcement and the mechanically mixed layer protection, TiC/Ni3Al‐coated parts demonstrated superior wear resistance and lower friction coefficient while compared with Ni3Al‐coated parts and H13 steel. [ABSTRACT FROM AUTHOR]

Abstract: Zinc‐nickel alloy coatings are electrodeposited on carbon steel from chloride bath using a technique of chronopotentiometry at different temperatures. The elemental composition and surface morphology analysis of zinc‐nickel coated samples are done using scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy. The coated samples are immersed in 3.5 wt.% sodium chloride solution and measurements of corrosion rate are done using linear polarization resistance. Scanning electron microscopy results show that deposition temperature variation has a strong effect which changes the surface morphology and elemental composition of zinc‐nickel alloy coatings. The nickel content in the electrodeposited zinc‐nickel alloy coatings increases with increasing deposition temperature. Uniformity and compactness of the coatings decrease with an increasing temperature. Cracks intensity increases with increasing deposition temperature which is attributed to internal stress due to factors that might be related to hydrogen evolution reaction. The linear polarization resistance results correlated with the morphology and compositional properties of zinc‐nickel alloy coatings deposited at different temperatures, that with an increase deposition temperature, corrosion resistance decreases. Zinc‐nickel alloy coatings with high corrosion resistance, compact and uniform morphology with less crack, and nickel content within the range of 12 wt.% to 15 wt.% are achieved with deposited coating at 25 °C. [ABSTRACT FROM AUTHOR]

Electrodes are ideal substrates for surface localized self-assembly processes. Spatiotemporal control over such processes is generally directed through the release of ions generated by redox reactions occurring specifically at the electrode. The so-used gradients of ions proved their effectiveness over the last decade but are in essence limited to material-based electrodes, considerably reducing the scope of applications. Herein is described a strategy to enzymatically generate proton gradients from non-conductive surfaces. In the presence of oxygen, immobilization of glucose oxidase (GOx) on a multilayer film provides a flow of protons through enzymatic oxidation of glucose by GOx. The confined acidic environment located at the solid-liquid interface allows the self-assembly of Fmoc-AA-OH (Fmoc=fluorenylmethyloxycarbonyl and A=alanine) dipeptides into β-sheet nanofibers exclusively from and near the surface. In the absence of oxygen, a multilayer nanoreactor containing GOx and horseradish peroxidase (HRP) similarly induces Fmoc-AA-OH self-assembly. [ABSTRACT FROM AUTHOR]

Emscher sewer, lot 40 - Segmental lining with special demands on the concrete The Emscher sewer is for now the largest infrastructure project in North Rhine-Westphalia. The first planning for the project with an actual budget of EUR 5.3 billion began in 1992. This process lasted 16 years until 2008 the building was approved. The Emscher cooperative in conjunction with the Association of the Lippe association is the largest association of water economy in Germany. The first pipe jacking operations for the Bottrop section between the sewage treatment plant of Bottrop and the Bernemündung in the so-called construction section (BA) 20 started in 2011. Work for the production of the largest section between the Nettebach in Dortmund and Bottrop plant known as stage BA 30 began in the spring of 2012. Underground work of the BA 40 from the Bernemündung began as the last part up to the pumping station of Oberhausen in 2014. This was also the conclusion of the underground work on 12 June 2017. In just 5 years, 73 km at depths of between 8 and 40 meters were produced at the main collective as a whole. The BA 40 is a special construction site, because it was not build in the pipe-jacking techniques, but as a tunnel with segmental lining of in total 20 km. As the central sewage system for 2.2 million inhabitants in the catchment area of the Emscher, the Emscher sewer has to be protected especially against chemical attacks, in particular against biogenic sulfuric acid. [ABSTRACT FROM AUTHOR]