Linköping Electronic Press Workshop and Conference Collection
The YSZ/mullite composite coatings have been given an impression for improved high temperature re... more The YSZ/mullite composite coatings have been given an impression for improved high temperature resistance over YSZ coatings under severe service conditions and should be investigated further for its possible use in thermal barrier coating (TBC) systems. In this study, a composite thermal barrier coating made from a combination of YSZ and mullite (wt%25 to 50) was investigated. Powders of each powders were mechanically mixed together and then sprayed on superalloy substrates. Microstructure and mechanical behavior relationship of these composite coatings were investigated. Crystallinity and phase ratios were determined by XRD analysis. Results showed that mullite addition improved the mechanical behaviour of YSZ coating under high temperature conditions.
Magnesium and its alloys are widely used in many industrial applications because of their high sp... more Magnesium and its alloys are widely used in many industrial applications because of their high specific strength (strength/density) ratio. However, these applications are still restricted by the relatively poor surface resistance of these materials. To overcome the inherent drawbacks a useful solution is to deposit a protective coating on the magnesium alloys. The sol-gel process is an effective method for fabricating oxide films on a magnesium alloy in order to produce a higher corrosion resistance. The objective of this study is to comparatively investigate the process and properties of repeated sol-gel oxide (ZrO2, Al2O3) coatings. The coatings were characterized by SEM, XRD, ellipsometry and the effects of the process on their properties were comparatively analysed. Keywords: sol-gel, oxide films, magnesium alloy Magnezij in njegove zlitine se uporabljajo v vrsti industrij zaradi visoke specifi~ne trdnosti (razmerje trdnost -gostota). Vendar pa je industrijska uporaba omejena za...
Non stick coatings is widely used in many industries because of having low coefficient of frictio... more Non stick coatings is widely used in many industries because of having low coefficient of friction, high corrosion resistance, dielectric strength, high temperature resistance according to other polymer sand a wide operating temperature range characteriristics. But the most important disadvantage is the low abrasion resistance. In this study to increase the abrasion resistance, non stick components were mixed with nano silver and characterization was realized on the teflon coating. As results, nano silver particles reinforced the non-stick coating improved its tribological properties and abrasion resistance. Industrial test results in accordance with the home and hand tools can be used in the composition of a coating successfully was formed. *
The last century has born witness to the rapid development of science and technology in the field... more The last century has born witness to the rapid development of science and technology in the field of synthetic polymers. The growth rate of polymer technology is over than 10% in developed and developing countries. In the years ahead, 300-400 million tons of annual world production of polymer and usage of polymeric materials as alternative materials in place of other materials in many applications are expected. Currently, advanced engineering polymers play an important role in applications due to their specific and outstanding features in contrast to the conventional polymers which are produced in large capacities and are used nearly hundreds of tons in daily life like PE, PP, PS, PVC, etc. Polymeric coating are used as anti-corrosion for pipelines and they are also used in ship hulls, antibacterial surfaces, decorative applications, imperviousness, tightness, flame-retardant applications, radio frequency barrier coatings, electrical insulation and in many other metal constructions....
Polymeric textile cords, steel cords and steel cables are mainly reinforcing materials that are u... more Polymeric textile cords, steel cords and steel cables are mainly reinforcing materials that are used in tire production. Polymeric textile cords such as Polyester (PEs), Nylon, Aramid and Rayon are commonly treated with bi-functional resorcinol formaldehyde latex (RFL) to obtain desired adhesion to rubber matrix. PEs cords are known as their poor adhesion to both RFL and rubber compounds due to limited reactivity on the surface and poor reaction extent between methylol and hydroxyl groups of RFL. Increasing carboxyl content on PEs surface or in the rubber compound is one of the best strategies to overcome this adhesion problem. Liquid rubbers, which can co-vulcanize with solid rubbers, are also strong alternatives of process oils with their excellent plasticizing effect without deterioration in mechanical properties of the resulting material. Co-vulcanization also improves the stability of this additive and prevents possible bleeding and migration during service life of the tire. In...
Flame spraying of polymers allows obtaining functional coatings for protecting against wear and c... more Flame spraying of polymers allows obtaining functional coatings for protecting against wear and corrosion. Among many engineering polymers, the Ethylene-Vinyl Acetate (EVA) copolymer attracts attention with its superior mechanical and chemical properties. EVA, which has high chemical resistance, high impact resistance and mechanical flexibility, high friction coefficient, is among the candidate coating material that can be used in aerospace, automotive, marine, chemical and manufacturing industries to protect metallic surfaces. The use of polymeric coatings in applications is often restricted when large surfaces need to be coated or if the coating needs to be applied in the openair field. Flame spraying is one of the most cost-effective methods in the production of polymeric coatings. The curing process and solvent use required in conventional polymeric coating applications are not required in thermal spray coating applications. Contact of polymeric surfaces with solid surfaces and ...
Plasma sprayed thermal barrier coatings (TBCs) are widely used in gas turbines to reduce thermal ... more Plasma sprayed thermal barrier coatings (TBCs) are widely used in gas turbines to reduce thermal effect and increase turbine efficiency. Depending on the application of plasma spray coating, different characteristics are important but there are some characteristics that are the same for all plasma spray applications: thickness, porosity, microstructure, presence of unmelted particles, cracks and oxides, microhardness and bond strength. The poor bonding between splats and the imperfections in the form of pores or thermal cracks cause the thermo-mechanical property values of plasma spray coatings. Bond strengths of TBCs were tested with the standard test method ASTM C 633. Porosity and unmelted particles ratio generally decreases adhesion tensile test values since a pore of critical size can induce a macroscopic failure with tensile stress applied. It was observed that the spray parameters: plasma gas flow rates, plasma current , powder feed rate and spray distance are important effec...
The twin-wire electrical arc spraying (TWAS) process is widely used for worn-out surface restorat... more The twin-wire electrical arc spraying (TWAS) process is widely used for worn-out surface restoration and the corrosion protection of metallic constructions. The industrial benefit of arc spray coatings is the possibility of cost-effective coating solutions to minimize corrosion problems. However, the wear resistance of metallic (such as Al, Cu and its alloys) arc sprayed coatings is inadequate. Alloys including Cu-Al intermetallic coatings are new candidates for use in tribological environments because of the combination of low cost and a remarkable resistance to abrasion under different working conditions. In this study the tribological properties of Al-Cu twin-wire arc-spray coatings are investigated in dry sliding test conditions depending on the load and the sliding distance.
Linköping Electronic Press Workshop and Conference Collection
The YSZ/mullite composite coatings have been given an impression for improved high temperature re... more The YSZ/mullite composite coatings have been given an impression for improved high temperature resistance over YSZ coatings under severe service conditions and should be investigated further for its possible use in thermal barrier coating (TBC) systems. In this study, a composite thermal barrier coating made from a combination of YSZ and mullite (wt%25 to 50) was investigated. Powders of each powders were mechanically mixed together and then sprayed on superalloy substrates. Microstructure and mechanical behavior relationship of these composite coatings were investigated. Crystallinity and phase ratios were determined by XRD analysis. Results showed that mullite addition improved the mechanical behaviour of YSZ coating under high temperature conditions.
Magnesium and its alloys are widely used in many industrial applications because of their high sp... more Magnesium and its alloys are widely used in many industrial applications because of their high specific strength (strength/density) ratio. However, these applications are still restricted by the relatively poor surface resistance of these materials. To overcome the inherent drawbacks a useful solution is to deposit a protective coating on the magnesium alloys. The sol-gel process is an effective method for fabricating oxide films on a magnesium alloy in order to produce a higher corrosion resistance. The objective of this study is to comparatively investigate the process and properties of repeated sol-gel oxide (ZrO2, Al2O3) coatings. The coatings were characterized by SEM, XRD, ellipsometry and the effects of the process on their properties were comparatively analysed. Keywords: sol-gel, oxide films, magnesium alloy Magnezij in njegove zlitine se uporabljajo v vrsti industrij zaradi visoke specifi~ne trdnosti (razmerje trdnost -gostota). Vendar pa je industrijska uporaba omejena za...
Non stick coatings is widely used in many industries because of having low coefficient of frictio... more Non stick coatings is widely used in many industries because of having low coefficient of friction, high corrosion resistance, dielectric strength, high temperature resistance according to other polymer sand a wide operating temperature range characteriristics. But the most important disadvantage is the low abrasion resistance. In this study to increase the abrasion resistance, non stick components were mixed with nano silver and characterization was realized on the teflon coating. As results, nano silver particles reinforced the non-stick coating improved its tribological properties and abrasion resistance. Industrial test results in accordance with the home and hand tools can be used in the composition of a coating successfully was formed. *
The last century has born witness to the rapid development of science and technology in the field... more The last century has born witness to the rapid development of science and technology in the field of synthetic polymers. The growth rate of polymer technology is over than 10% in developed and developing countries. In the years ahead, 300-400 million tons of annual world production of polymer and usage of polymeric materials as alternative materials in place of other materials in many applications are expected. Currently, advanced engineering polymers play an important role in applications due to their specific and outstanding features in contrast to the conventional polymers which are produced in large capacities and are used nearly hundreds of tons in daily life like PE, PP, PS, PVC, etc. Polymeric coating are used as anti-corrosion for pipelines and they are also used in ship hulls, antibacterial surfaces, decorative applications, imperviousness, tightness, flame-retardant applications, radio frequency barrier coatings, electrical insulation and in many other metal constructions....
Polymeric textile cords, steel cords and steel cables are mainly reinforcing materials that are u... more Polymeric textile cords, steel cords and steel cables are mainly reinforcing materials that are used in tire production. Polymeric textile cords such as Polyester (PEs), Nylon, Aramid and Rayon are commonly treated with bi-functional resorcinol formaldehyde latex (RFL) to obtain desired adhesion to rubber matrix. PEs cords are known as their poor adhesion to both RFL and rubber compounds due to limited reactivity on the surface and poor reaction extent between methylol and hydroxyl groups of RFL. Increasing carboxyl content on PEs surface or in the rubber compound is one of the best strategies to overcome this adhesion problem. Liquid rubbers, which can co-vulcanize with solid rubbers, are also strong alternatives of process oils with their excellent plasticizing effect without deterioration in mechanical properties of the resulting material. Co-vulcanization also improves the stability of this additive and prevents possible bleeding and migration during service life of the tire. In...
Flame spraying of polymers allows obtaining functional coatings for protecting against wear and c... more Flame spraying of polymers allows obtaining functional coatings for protecting against wear and corrosion. Among many engineering polymers, the Ethylene-Vinyl Acetate (EVA) copolymer attracts attention with its superior mechanical and chemical properties. EVA, which has high chemical resistance, high impact resistance and mechanical flexibility, high friction coefficient, is among the candidate coating material that can be used in aerospace, automotive, marine, chemical and manufacturing industries to protect metallic surfaces. The use of polymeric coatings in applications is often restricted when large surfaces need to be coated or if the coating needs to be applied in the openair field. Flame spraying is one of the most cost-effective methods in the production of polymeric coatings. The curing process and solvent use required in conventional polymeric coating applications are not required in thermal spray coating applications. Contact of polymeric surfaces with solid surfaces and ...
Plasma sprayed thermal barrier coatings (TBCs) are widely used in gas turbines to reduce thermal ... more Plasma sprayed thermal barrier coatings (TBCs) are widely used in gas turbines to reduce thermal effect and increase turbine efficiency. Depending on the application of plasma spray coating, different characteristics are important but there are some characteristics that are the same for all plasma spray applications: thickness, porosity, microstructure, presence of unmelted particles, cracks and oxides, microhardness and bond strength. The poor bonding between splats and the imperfections in the form of pores or thermal cracks cause the thermo-mechanical property values of plasma spray coatings. Bond strengths of TBCs were tested with the standard test method ASTM C 633. Porosity and unmelted particles ratio generally decreases adhesion tensile test values since a pore of critical size can induce a macroscopic failure with tensile stress applied. It was observed that the spray parameters: plasma gas flow rates, plasma current , powder feed rate and spray distance are important effec...
The twin-wire electrical arc spraying (TWAS) process is widely used for worn-out surface restorat... more The twin-wire electrical arc spraying (TWAS) process is widely used for worn-out surface restoration and the corrosion protection of metallic constructions. The industrial benefit of arc spray coatings is the possibility of cost-effective coating solutions to minimize corrosion problems. However, the wear resistance of metallic (such as Al, Cu and its alloys) arc sprayed coatings is inadequate. Alloys including Cu-Al intermetallic coatings are new candidates for use in tribological environments because of the combination of low cost and a remarkable resistance to abrasion under different working conditions. In this study the tribological properties of Al-Cu twin-wire arc-spray coatings are investigated in dry sliding test conditions depending on the load and the sliding distance.
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