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1. Aspects to be considered when making innovation out of promising research results in surface technology [2019]

  • Leisner, Peter, Johansson, E., Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning, RISE - Research Institutes of Sweden, Säkerhet och transport, Elektronik, and RISE - Research Institutes of Sweden
  • Transactions of the Institute of Metal Finishing. 97(2):67-72
Subjects
Engineering and Technology, Materials Engineering, Manufacturing, Surface and Joining Technology, Teknik och teknologier, Materialteknik, Bearbetnings-, yt- och fogningsteknik, Electric connectors, Printed circuit boards, Cost-efficient, Customer expectation, Economic potentials, Electrical connectors, Research results, Surface technology, Technology readiness levels, Uncertainty and risks, Surface treatment, Natural Sciences, and Naturvetenskap
Abstract
In the eyes of industrialists, scientists often exaggerate the economic potential of their findings. The industrialists know that developing a new technology to production is associated with uncertainty and risks. To elucidate the challenges faced by the surface treatment industry, this paper discusses aspects that should be considered when making innovation out of promising research results. The Technology Readiness Level (TRL) metric for assessing maturity of a technology is discussed and exemplified. Additional risks of fluid character such as legislation, price of raw material and customer expectations are also discussed. Even though, the subject is of general relevance, the present discussion refers to surface technology and examples are given from copper plating of printed circuit boards, and durable and cost-efficient coatings on electrical connectors.

2. Effects of Surface Finish on the Initial Oxidation of HVAF-sprayed NiCoCrAlY Coatings [2019]

  • Zhang, Pimin, Sadeghimeresht, Esmaeil, Chen, Shula, Li, Xin-Hai, Markocsan, Nicoclaie, Joshi, Shrikant, Chen, Weimin, Buyanova, Irina A, Peng, Ru Lin, Sadeghi, Esmaeil, Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Konstruktionsmaterial, Linköpings universitet, Tekniska fakulteten, Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi, Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT), and Högskolan Väst, Institutionen för ingenjörsvetenskap, Forskningsmiljön produktionsteknik(PTW)
  • Surface & Coatings Technology. 364:43-56
Subjects
Engineering and Technology, Materials Engineering, Teknik och teknologier, Materialteknik, Oxidation, Transient ot alpha transformation, Surface treatment, Polishing, Shot-peening, Photo-stimulated liminescence spectroscopy, Manufacturing, Surface and Joining Technology, Bearbetnings-, yt- och fogningsteknik, Manufacturing and materials engineering, Produktions- och materialteknik, Transient to alpha transformation, and Photo-stimulated luminescence spectroscopy
Abstract
p data-select-like-a-boss="1">Oxide scale formed on HVAF-sprayed NiCoCrAlY coatings and the effect ofsurface treatmentwere investigated by a multi-approach study combining photo-stimulatedluminescence, microstructural observation and mass gain. The initialoxidationbehaviour of as-sprayed, polished and shot-peened coatings at 1000 °C is studied. Both polished and shot-peened coatings exhibited superior performance due to rapid formation of α-Al2O3fully covering the coating and suppressing the growth oftransientalumina, assisted by a high density of α-Al2O3nuclei on surface treatment induced defects. Moreover, the fast development of a two-layer alumina scale consisting of an inward-grown inner α-Al2O3layer and an outer layer transformed from outward-grown transient alumina resulted in a higher oxide growth rate of the as-sprayed coating.

3. Investigation and application of mussel adhesive protein nanocomposite film-forming inhibitor for reinforced concrete engineering [2019]

  • Zhang, Fan, Chen, Chengdong, Hou, Ruiqing, Li, Jing, Cao, Yanhui, Dong, Shigang, Lin, Changjian, Pan, Jinshan, and KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap
  • Corrosion Science. 153:333-340
Subjects
Engineering and Technology, Materials Engineering, Teknik och teknologier, Materialteknik, Mussel adhesive protein, Nanocomposite, Corrosion protection, Self-healing, Film forming, Reinforced concrete, Chemical Engineering, Corrosion Engineering, Kemiteknik, Korrosionsteknik, Adhesives, Electrochemical corrosion, Molluscs, Morphology, Nanocomposites, Pitting, Proteins, Self-healing materials, Steel corrosion, Surface treatment, Thin films, Concrete pore solutions, Film forming inhibitors, Film-forming, Mussel adhesive proteins, Nanocomposite thin films, Self-healing abilities, Surface pre-treatments, and Nanocomposite films
Abstract
A mussel adhesive protein based nanocomposite thin film was produced to be applied as surface pre-treatment or primer on rebars of reinforced concrete. The film deposition and drying processes were investigated to enhance the corrosion protection, and facilitate large-scale industrial applications. The morphology, chemical composition and microstructure of the film were characterised with SEM, EDS, Micro-IR and AFM techniques. EIS results suggested the film provides excellent and increased corrosion protection for the carbon steel in mild and extreme concrete pore solutions. In-situ AFM results demonstrated the self-healing ability of the film to the pitting corrosion.

4. Microstructural Characterization of Sulfurization Effects in Cu(In,Ga)Se-2 Thin Film Solar Cells [2019]

  • Aboulfadl, Hisham, Keller, Jan, Larsen, Jes K, Thuvander, Mattias, Riekehr, Lars, Edoff, Marika, Platzer Björkman, Charlotte, and Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik
  • Microscopy and Microanalysis. 25(2):532-538
Subjects
Natural Sciences, Physical Sciences, Condensed Matter Physics, Naturvetenskap, Fysik, Den kondenserade materiens fysik, atom probe, Cu(In, Ga)Se-2, solar cells, surface treatment, thin films, Oorganisk kemi, Inorganic Chemistry, Materialkemi, Materials Chemistry, Annan kemi, Other Chemistry Topics, and Cu(In,Ga)Se 2
Abstract
Surface sulfurization of Cu(In,Ga)Se-2 (CIGSe) absorbers is a commonly applied technique to improve the conversion efficiency of the corresponding solar cells, via increasing the bandgap towards the heterojunction. However, the resulting device performance is understood to be highly dependent on the thermodynamic stability of the chalcogenide structure at the upper region of the absorber. The present investigation provides a high-resolution chemical analysis, using energy dispersive X-ray spectrometry and laser-pulsed atom probe tomography, to determine the sulfur incorporation and chemical re-distribution in the absorber material. The post-sulfurization treatment was performed by exposing the CIGSe surface to elemental sulfur vapor for 20 min at 500 degrees C. Two distinct sulfur-rich phases were found at the surface of the absorber exhibiting a layered structure showing In-rich and Ga-rich zones, respectively. Furthermore, sulfur atoms were found to segregate at the absorber grain boundaries showing concentrations up to similar to 7 at% with traces of diffusion outwards into the grain interior.

5. Simulation of Electrostatic Rotary Bell Spray Painting in Automotive PAint Shops [2013]

  • Mark, Andreas, Andersson, Björn O, Tafuri, Sebastian, Engström, Klas, Söröd, Henrik, Edelvik, Fredrik, and Carlson, Johan
  • Atomization and Sprays. 23(1):25-45
Subjects
Beräkningsmatematik, Computational Mathematics, Strömningsmekanik och akustik, Fluid Mechanics and Acoustics, surface treatment, multiphysics, and immersed boundary method
Abstract
A new framework for simulation of electrostatic spray painting is proposed based on novel algorithms for coupled simulations of air flow, electromagnetic fields, and paint droplets. Particularly important for the computational efficiency is the Navier-Stokes solver. The incompressible solver is based on a finite volume discretization on a dynamic Cartesian octree grid and unique immersed boundary methods are used to model the presence of objects in the fluid. This enables modeling of moving objects at virtually no additional computational cost and greatly simplifies preprocessing by avoiding the cumbersome generation of a body-conforming mesh. To validate the simulation framework an extensive measurement campaign has been performed. Several test plates and car fenders were painted with different process conditions and robot paths. The same cases were then simulated and overall the agreement between simulations and experiments are remarkably good. The very efficient implementation gives a major improvement of computational speed compared to other approaches and makes it possible to simulate spray painting of a full car in just a few hours on a standard computer.

6. Autoregulation of thromboinflammation on biomaterial surfaces by a multicomponent therapeutic coating [2013]

  • Nilsson, Per H., N. Ekdahl, Kristina, Magnusson, Peetra U., Qu, Hongchang, Iwata, Hiroo, Ricklin, Daniel, Hong, Jaan, Lambris, John D., Nilsson, Bo, Teramura, Yuji, and Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Klinisk immunologi
  • Biomaterials. 34(4):985-994
Subjects
Medical and Health Sciences, Medicin och hälsovetenskap, Apyrase, Coagulation, Complement, Factor H-binding peptide, Poly(ethylene glycol) (PEG), Surface modification, Autoregulations, Biological response, Biomaterial surfaces, Blood contact, Complement systems, H-binding, Hemocompatibility, Hybrid surface, Innate immunity, Modified surfaces, Multicomponents, Whole blood, Biological materials, Biomaterials, Peptides, Polyethylene glycols, Surface treatment, Surfaces, 5C6 peptide, biomaterial, complement factor H, macrogol, peptide, unclassified drug, article, autoregulation, biotinylation, endothelium cell, erythrocyte, human, inflammation, multicomponent therapeutic coating, peptide synthesis, porcine aortic endothelial cell, priority journal, protein immobilization, and thromboinflammation
Abstract
Activation of the thrombotic and complement systems is the main recognition and effector mechanisms in the multiple adverse biological responses triggered when biomaterials or therapeutic cells come into blood contact. We have created a surface which is auto-protective to human innate immunity by combining three fundamentally different strategies, all developed by us previously, which have been shown to induce substantial, but incomplete hemocompatibility when used separately. In summary, we have conjugated a factor H-binding peptide; and an ADP-degrading enzyme; using a PEG linker on both material and cellular surfaces. When exposed to human whole blood, factor H was specifically recruited to the modified surfaces and inhibited complement attack. In addition, activation of platelets and coagulation was efficiently attenuated, by degrading ADP. Thus, by inhibiting thromboinflammation using a multicomponent approach, we have created a hybrid surface with the potential to greatly reduce incompatibility reactions involving biomaterials and transplantation.

7. Beyond Massive-MIMO: The Potential of Data-Transmission with Large Intelligent Surfaces [2018]

  • Hu, Sha, Rusek, Fredrik, Edfors, Ove, Lunds universitet, Kommunikationsteknologi, Lund University, Communications Engineering, Lunds universitet, ELLIIT: the Linköping-Lund initiative on IT and mobile communication, and Lund University, ELLIIT: the Linköping-Lund initiative on IT and mobile communication
  • IEEE Transactions on Signal Processing. 66(10):2746-2758
Subjects
Teknik, Elektroteknik och elektronik, Kommunikationssystem, Engineering and Technology, Electrical Engineering, Electronic Engineering, Information Engineering, Communication Systems, 2D sampling, Hankel transform, hexagonal lattice, independent signal dimension, intersymbol interference (ISI), Large intelligent surface (LIS), Lattices, Lenses, line-of-sight (LOS), massive multiinput multi-output (MIMO), MIMO communication, normalized capacity, Receiving antennas, Surface treatment, and Surface waves
Abstract
In this paper, we consider the potential of data-transmission in a system with a massive number of radiating and sensing elements, thought of as a contiguous surface of electromagnetically active material. We refer to this as a Large Intelligent Surface (LIS). The "LIS" is a newly proposed concept, which conceptually goes beyond contemporary massive MIMO technology, and arises from our vision of a future where man-made structures are electronically active with integrated electronics and wireless communication making the entire environment "intelligent". Firstly, we consider capacities of single-antenna autonomous terminals communicating to the LIS where the entire surface is used as a receiving antenna-array in a perfect line-of-sight (LOS) propagation environment. Under the condition that the surface-area is sufficiently large, the received signal after a matched-filtering (MF) operation can be closely approximated by a sinc-function-like intersymbol interference (ISI) channel. Secondly, we analyze a normalized capacity measured per unit-surface, for a fixed transmit power per volume-unit with different terminal-deployments. As terminal-density increases, the limit of the normalized capacity [nats/s/Hz/volume-unit] achieved when wavelength $\lambda$ approaches zero is equal to half of the transmit power per volume-unit divided by noise spatial power spectral density (PSD). Thirdly, we show that the number of independent signal dimensions that can be harvested per meter deployed surface is $2/\lambda$ for one-dimensional terminal-deployment, and $\pi/\lambda^{2}$ per square meter for two and three dimensional terminal-deployments. Lastly, we consider implementations of the LIS in the form of a grid of conventional antenna-elements, and show that the sampling lattice that minimizes the surface-area and simultaneously obtains one independent signal dimension for every spent antenna is the hexagonal lattice.

8. A Method for Determining Trap Distributions of Specific Channel Surfaces in InGaAs Tri-gate MOSFETs [2018]

  • Netsu, Seiko, Hellenbrand, Markus, Zota, Cezar B., Miyamoto, Yasuyuki, Lind, Erik, Lunds universitet, Nanoelektronik, Lund University, Nano Electronics, Lunds universitet, NanoLund, Lund University, NanoLund, Lunds universitet, Institutionen för elektro- och informationsteknik, and Lund University, Department of Electrical and Information Technology
  • IEEE Journal of the Electron Devices Society. 6:408-412
Subjects
Electron traps, FinFETs., high-κ, Hysteresis, hysteresis, III-V, InGaAs, inter face trap, Logic gates, Mathematical model, MOSFET, MOSFETs, Multi-gate, Surface fitting, Surface treatment, trap density, Teknik, Elektroteknik och elektronik, Annan elektroteknik och elektronik, Engineering and Technology, Electrical Engineering, Electronic Engineering, Information Engineering, and Other Electrical Engineering, Electronic Engineering, Information Engineering
Abstract
We present a method for estimating the trap distributions on each of the surfaces in a multi-gate MOSFET. We perform I-V hysteresis measurements on InGaAs Tri-gate MOSFETs with various channel widths (25, 60 and 100 nm) from which top surface and side wall trap distributions are determined. We show that the total trap distribution of a device can be expressed as a linear combination of the top surface and side wall trap distributions. The results show that the minimum trap density of the top InGaAs (100) surface is smaller than that of the 110 side walls by almost an order of magnitude. Since the nanowire constituting the channel in these devices is selectively regrown, rather than etched out, the different trap distributions can be explained by the specific surface chemistries of two surfaces.

9. Offshoring and backshoring of surface finishing from the perspective of the Nordic countries [2019]

  • Leisner, Peter, Nielsen, Lars Pleth, Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning, and RISE - Research Institutes of Sweden, Säkerhet och transport, Elektronik
  • Transactions of the Institute of Metal Finishing. 97(2):54-56
Subjects
Engineering and Technology, Mechanical Engineering, Production Engineering, Human Work Science and Ergonomics, Teknik och teknologier, Maskinteknik, Produktionsteknik, arbetsvetenskap och ergonomi, Materials Engineering, Manufacturing, Surface and Joining Technology, Materialteknik, Bearbetnings-, yt- och fogningsteknik, finishing, Market trends, Scandinavia, supplier, surface technology, Nordic countries, Production quality, Surface finishing, Surface finishing industry, Surface treatment, Natural Sciences, and Naturvetenskap
Abstract
Backshoring of production to Western Europe has become an increasingly important trend after decades of offshoring. The subject is introduced by a general discussion followed by a specific analysis of the Nordic surface finishing industry. The main finding is that production quality is the main driver for backshoring of surface finishing.

10. Localised corrosion and atmospheric corrosion of stainless steels [2019]

  • Hägg Mameng, Sukanya and KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap
  • TRITA-CBH-FOU.
Subjects
Engineering and Technology, Other Engineering and Technologies, Other Engineering and Technologies not elsewhere specified, Teknik och teknologier, Annan teknik, Övrig annan teknik, stainless steel, localised corrosion, atmospheric corrosion, alloy composition, surface finish, surface roughness, surface treatment, surface orientation, contamination, chloride, sulphate, temperature, chlorination, exposure conditions., Kemi, and Chemistry
Abstract
This research is focused on defining limiting conditions for corrosion of stainless steels. The aim of the first part (Papers I-IV) was to understand the role of alloying level and environmental parameters on localised corrosion in aqueous conditions. Testing was done with a combination of short-term electrochemical and long-term immersion experiments. Results show that the chloride ion concentration and temperature are the main factors that affect the localised corrosion resistance. The presence of residual chlorine is also significant, since it leads to the ennoblement of the corrosion potential. If the corrosion potential exceeds the breakdown potential, the stainless steel will suffer from localised corrosion. Oxygen content and pH were identified as additional factors influencing the corrosivity of the environment.The aim of second part (Papers V-VIII) was to present information about the effect of alloying level, surface condition and environmental conditions on atmospheric corrosion resistance in Middle-East environments. Field exposure tests were performed and supplemented by laboratory aqueous corrosion tests. Results demonstrate that a higher alloying level (in both the bulk material and the surface), plus a smoother and cleaner surface gave an improvement in the corrosion performance and resistance to aesthetic degradation. Chloride and sulphate are the main surface contaminants found in the Middle East atmosphere. Stainless steels exposed in sheltered conditions showed a better atmospheric corrosion resistance than in open conditions. Three factors are considered to contribute to this difference: a very low rainfall, more condensation leading to corrosion in the open conditions and a higher level of beneficial sulphate in the deposits in sheltered conditions. The results showed a reasonable correlation between laboratory pitting corrosion tests and atmospheric field tests.The results from this thesis provide reference data to aid selection of appropriate stainless steel grades. Results can also be used to help understand the limits for use of stainless steels in different conditions in both aqueous environments and in the atmosphere.
Denna avhandling inriktar sig på att definiera gränser för korrosion hos rostfria stål. Syftet med den första delen (Artikel I-IV) var att förstå inverkan av legeringssammansättning och miljöparametrar på lokal korrosion i vattenlösningar. En kombination av elektrokemiska korttidsförsök och långvarig provning har utförts. Resultaten visar att kloridhalten och temperaturen är de två viktigaste faktorerna som påverkar den lokala korrosionsbeständigheten hos rostfritt stål. Närvaro av kvarvarande klor är också en betydande faktor som leder till att korrosionspotentialen ökar. Om korrosionspotentialen når genombrottspotentialen drabbas det rostfria stålet av lokal korrosion. Syreinnehåll och pH visade sig vara ytterligare faktorer som påverkar miljöns korrosivitet. Syftet med den andra delen (Artikel V-VIII) var att presentera information om hur olika legeringsämnen, yttillstånd och miljöparametrar påverkar den atmosfäriska korrosionsbeständigheten i Mellanöstern. Fälttester har utförts i kombination med korrosionstester i laboratoriet. Resultaten visar att ett högre legeringsinnehåll (i både bulkmaterialet och på ytan), samt en jämnare och rengjord yta gav en förbättring av korrosionsegenskaperna. Klorid och sulfat är de två huvudsakliga föroreningarna som finns i Mellanösterns atmosfär. Rostfria stål exponerade under skyddade förhållanden uppvisade en bättre korrosionsbeständighet än under öppna förhållanden. Tre faktorer anses bidra till denna skillnad: en mycket låg nederbörd, mer kondens som leder till korrosion under öppna förhållanden och en högre nivå av gynnsamt sulfat i avlagringar under skyddade förhållanden. Resultaten visade också en rimlig korrelation mellan laboratorietester och de atmosfäriska fälttesterna. Resultaten från forskningen ger referensdata som kan användas som stöd för materialval och för att lättare kunna välja rätt rostfri stålsort. Resultaten kan också användas för att förstå gränser för rostfritt stål gällande lokal korrosion i olika miljöer.

11. Study of particle-current-electrocrystallization interactions in electroplating of Ni/SiC coatings [2019]

  • Pinate, Santiago and Högskolan i Jönköping, Tekniska Högskolan, JTH, Material och tillverkning
  • JTH Dissertation Series.
Subjects
Engineering and Technology, Mechanical Engineering, Teknik och teknologier, Maskinteknik, Composite coatings, Nanoparticles, Electrocrystallisation, Microstructure, Surface treatment, Pulse plating, Ultrasound agitation, Kompositbeläggningar, Nanopartiklar, Elektrokristallisering, Mikrostruktur, Ytbehandling, Pulsplätering, and Ultraljudsomrörning
Abstract
Composite coatings have great potential due to the possibility to combine properties of two different materials in one coating. This way, new surface properties can be tailored and applied to any material's surface. Among different manufacturing routes, electrodeposition has the biggest potential in creating composite metal matrix coatings, especially nanocomposites. Nevertheless, there is a knowledge gap between the deposition of composite coatings in laboratory conditions, described in the literature, and those that are now in place on an industrial level. While micro-composites have been industrialised for about ten years, the production of Ni/SiC nanocomposite coatings by electroplating is still far from an industrial manufacturing floor. This is due to the lack of understanding of the mechanisms of nanoparticles codeposition leading to scattering results.The production of nanocomposite coatings is much more sensitive to the process parameters compared to microcomposite. The correlation between parameters and their influence on the codeposition are still not fully identified and understood. The codeposition models proposed in the literature are only valid in specific conditions, but composite depositions behave differently, or even opposite if some of the variables are modified.The main objective of this work is to identify the particle-current-electrocrystallization interactions in the production of Ni/SiC nanocomposites. A series of experiments are designed to isolate single variables and identify the controlling parameters of these interactions and their impact on the final properties.In this thesis, the effect of current density, type of current and particles size are identified as primary variables controlling the metal crystallisation and coatings properties.Among many parameters, a specific current waveform in pulse reverse mode proved to increase the codeposition rate effectively, doubling the content of nanoparticles compared to other techniques. Ultrasound assistance is also considered as stirring method when particles are suspended in the deposition bath to increase their stability and dispersion. The effect of Ultrasound on the particles codeposition and metal crystallisation is studied and compared to silent condition.Moreover, a surface treatment for the particle has been proven successful in making any particle to behave similarly in the Ni deposition bath. Furthermore, the codeposition rate doubled or tripled compared to untreated ones thanks to this treatment. Both ultrasonic agitation and surface treatment reduce the formation of aggregates, improving the particle dispersion and metal microstructure thus increasing the final hardness.The work proved the synergistic effect between particle and metal microstructure which affected the final properties of the coating. Therefore, when tailoring the composite coating to improve hardness, it is not only the amount of the particles that should be considered but also their influence on the electrocrystallisation process.
Kompositbeläggning har stort potential tack vare möjligheten att kombinera två material i samma ytskikt. På detta sätt kan nya ytegenskaper skräddarsys och appliceras på ett materials yta. Elektrodeposition är den tillverkningsmetod som har störst potential att uppnå kompositbeläggningar, i synnerhet nanokompositer. Ett kunskapsgap existerar mellan elektrodeposition under laboratorieförhållanden, som beskrivet i vetenskaplig litteratur, och hur processen går till i industriell miljö. Medan industriell tillämpning av mikrokompositer pågått ungefär tio år, så har produktion av Ni/SiC nanokompositbeläggningar fortfarande inte nått fabriksgolvet. Detta är en konsekvens av bristande förståelse kring mekanismer för samdeposition av nanopartiklar som leder till varierande resultat.Produktion av nanokompositbeläggningar är mycket mer känslig för processparametrar jämfört med mikrokompositer. Korrelationer mellan parametrar och dess inverkan på samdeposition är fortfarande inte fullt identifierade och förstådda. Modeller för samdeposition som föreslås i vetenskaplig litteratur är endast giltiga under särskilda förhållanden. Kompositdeposition kan uppvisa avvikande eller till och med motsatt beteende om variabler förändras.Huvudmålet med detta arbete är att identifiera interaktioner mellan partikel, ström och elektrokristallisering under tillverkning av Ni/SiC nanokompositer. En serie av experiment är utvecklade för att isolera variabler och identifiera de parametrarna som kontrollerar dessa interaktioner och dess inverkan på ytans egenskaper.I denna avhandling identifieras strömtäthet, typ av ström, och partiklars storlek som primära variabler som kontrollerar metallkristallisering och beläggningens egenskaper.Bland många parametrar, visades en specifik vågform på strömmen i omvänd pulsläge öka samdepositionen effektivt, ledande till en fördubbling av andelen nanopartiklar jämfört med andra tekniker. Ultraljud tillämpades som metod för omrörning av depositionsbadet för förbättrad stabilitet och fördelning. Effekten av ultraljud på samdepositionen av metallkristallisering studeras och jämfört med tyst tillstånd.Dessutom har en ytbehandling för partiklarna visats framgångsrik för att få godtyckliga partiklar att bete sig likt Ni i depositionsbadet. Detta ledde till att samdepositionens takt ökade med en faktor av två till tre jämfört med obehandlade partiklar. Både ultraljud och ytbehandling av partiklarna ledde till minskad aggregation vilket förbättrade fördelningen av partiklar och metallstruktur och därigenom ökad hårdhet.Arbetet bevisar synergieffekten mellan partiklar och metallstruktur vilket påverkar beläggningens slutliga egenskaper. Vid utveckling av nya ytbeläggningar ska därför inte bara mängden partiklar beaktas utan även dess interaktion med elektrokristalliseringsprocessen.

12. Dimensional Scaling of Aqueous Ink Imbibition and Inkjet Printability on Porous Pigment Coated Paper-A Revisit [2018]

  • Swerin, Agne, RISE - Research Institutes of Sweden, Biovetenskap och material, Yta, process och formulering, and KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap
  • Industrial & Engineering Chemistry Research. 57(49):16684-16691
Subjects
Natural Sciences, Naturvetenskap, Capillarity, Capillary tubes, Paper, Pigments, Porous materials, Surface treatment, Coated paper, Functional surfaces, Isotropic media, Materials parameters, Mineral pigments, Primary factors, Simple fluids, Uncoated paper, Ink, Chemical Sciences, and Kemi
Abstract
A recently published dimensional scaling of infiltration of water-based inkjet fluids was used to revisit published inkjet printability data on mineral-pigment-based, inkjet-receptive coated papers. The dimensional scaling was developed using simple fluids on homogeneous isotropic media and applied on uncoated papers using complex inkjet fluids but so far has not been related to printability. It is shown that the scaling can also work for coated papers using commercial dye- and pigment-based inks with a suggested relation to printability as given by the color gamut area, in which the primary factor is the product of permeability and capillary pressure. A successful scaling suggests that inkjet printability can be predicted from flow and materials parameters, namely, porosity, viscosity, imbibed volume, permeability, and capillary pressure, and would be of general applicability in other areas of inkjet printing. The results further imply the usefulness of the approach in other functional surface modification using waterborne procedures on hard or soft porous materials.

13. Sulfurization of Co-Evaporated Cu(In,Ga)Se-2 as a Postdeposition Treatment [2018]

  • Larsen, Jes K, Keller, Jan, Lundberg, Olle, Jarmar, Tobias, Riekehr, Lars, Scragg, Jonathan J., Platzer Björkman, Charlotte, and Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets elektronik
  • IEEE Journal of Photovoltaics. 8(2):604-610
Subjects
Natural Sciences, Physical Sciences, Condensed Matter Physics, Naturvetenskap, Fysik, Den kondenserade materiens fysik, Engineering and Technology, Teknik och teknologier, Alloying, Cu(In, Ga)Se-2 (CIGSe), postdeposition treatment, surface treatment, and thin-film solar cells
Abstract
It is investigated if the performance of Cu(In,Ga)Se-2 (CIGSe) solar cells produced by co-evaporation can be improved by surface sulfurization in a postdeposition treatment. The expected benefit would be the formation of a sulfur/selenium gradient resulting in reduced interface recombination and increased open-circuit voltage. In the conditions used here it was, however, found that the reaction of the CIGSe layer in a sulfur environment results in the formation of a CuInS2 (CIS) surface phase containing no or very little selenium and gallium. At the same time, a significant pile up of gallium was observed at the CIGSe/CIS boundary. This surface structure was formed for a wide range of annealing conditions investigated in this paper. Increasing the temperature or extending the time of the dwell stage had a similar effect on the material. The gallium enrichment and CIS surface layer widens the surface bandgap and therefore increases the open-circuit voltage. At the same time, the fill factor is reduced, since the interface layer acts as an electron barrier. Due to the balance of these effects, the conversion efficiency could not be improved.

14. Localized wood surface modification, Part I: Method characterization [2017]

  • Elustondo, Diego, Myronycheva, Olena, Sundqvist, Bror, Karlsson, Olov, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik, and RISE - Research Institutes of Sweden, Bioekonomi
  • BioResources. 12(1):283-295
Subjects
Engineering and Technology, Mechanical Engineering, Other Mechanical Engineering, Teknik och teknologier, Maskinteknik, Annan maskinteknik, Träteknik, Wood Science and Engineering, Scots pine, Wood surface modification, Heating-and-cooling, Compression-and-expansion, Materials Engineering, Materialteknik, Coatings, Forestry, Wood, Full volume, Heating and cooling, Open process, Pinus sylvestris, Pressure treatments, Treatment temperature, Wood surfaces, Surface treatment, Processes, and Surfaces
Abstract
This study assesses the potential of an open process for treatment of European Scots pine (Pinus sylvestris) with chemicals that could potentially make the surfaces stronger, more dimensionally stable, or more durable, depending on the treatment solution. The method provides an intermediate solution between full volume impregnation by pressure treatment and superficial surface treatment by dipping. Figuratively speaking, the process creates the equivalent of a layer of coating applied below the wood surfaces rather than above. Two different techniques were compared, namely, heating-and-cooling (H & C) and compression-and-expansion (C & E). Taking into account that commercial suppliers recommend 0.15 to 0.25 L/m2 of coating in sawn wood and 0.1 to 0.15 L/m2 in planed wood surfaces, then this study demonstrates that the H & C method can impregnate an equivalent amount of solution under the surfaces in less than 15 min using treatment temperatures below 150 °C. © 2017 North Carolina State University.

15. Surface modification of solid wood by charring [2017]

  • Kymalainen, M., Hautamaki, S., Lillqvist, Kristiina, Segerholm, Kristoffer, Rautkari, L., Kymäläinen, Maija, Hautamäki, Saara, KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Byggvetenskap, Byggnadsmaterial, and RISE - Research Institutes of Sweden, Bioekonomi
  • Journal of Materials Science. 52(10):6111-6119
Subjects
Engineering and Technology, Civil Engineering, Teknik och teknologier, Samhällsbyggnadsteknik, Agricultural and Veterinary sciences, Agricultural Science, Forestry and Fisheries, Wood Science, Lantbruksvetenskap och veterinärmedicin, Lantbruksvetenskap, skogsbruk och fiske, Trävetenskap, solid wood, contact angle, heat conduction, heat transfer, moisture, surface treatment, weathering, wood product, and wooden building
Abstract
Most wooden structures for outdoor applications require repetitive maintenance operations to protect the surfaces from adverse effects of weathering. One-sided surface modification of boards with a relatively fast charring process has the potential to increase the durability and service life of wooden claddings. To assess some weathering-related effects on surface charred wood, spruce and pine sapwood were subjected to a series of long charring processes (30â120Âmin) at a moderate temperature of 250°C and to a short one (30Âs) at a high temperature of 400°C. The wettability and contact angles of treated samples were investigated, and the heat transfer was measured along with the micromorphological changes taking place in the material. The result revealed an increased moisture resistance of charred spruce sapwood and an increased water uptake of pine sapwood. The contact angles of both wood species improved compared to references. Heat conduction measurement revealed that only a thin section of the wood was thermally modified. Some micromorphological changes were recorded, especially on the inside walls of the lumina. The results show that spruce sapwood has an improved resistance towards moisture-induced weathering, but more studies are needed to unlock the potential of surface charred wood.

16. Fabrication and Kinetic Study of a Ferrihydrite-Modified BiVO4 Photoanode [2017]

  • Yu, F., Li, F., Yao, T., Du, J., Liang, Y., Wang, Y., Han, H., Sun, Licheng, KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD, KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi, and KTH, Skolan för informations- och kommunikationsteknik (ICT), Centra, Zhejiang-KTH Joint Research Center of Photonics, JORCEP
  • ACS Catalysis. 7(3):1868-1874
Subjects
Natural Sciences, Chemical Sciences, Materials Chemistry, Naturvetenskap, Kemi, Materialkemi, bismuth vanadate, ferrihydrite, passivation, photoanode, water splitting, Electrodes, Metals, Surface treatment, Bismuth vanadates, Ferrihydrites, Intensity modulated photocurrent spectroscopy (IMPS), Performance enhancements, Photo-anodes, Photon-to-current efficiencies, Reversible hydrogen electrodes, and Photoelectrochemical cells
Abstract
In spite of great progress in the surface modification of semiconductor photoelectrodes, the role of the metal oxide cocatalyst on photoelectrochemical (PEC) performance is still not well understood. In this study, ferrihydrite (Fh) as a novel cocatalyst was decorated on a wormlike nanoporous BiVO4 photoanode. A surface kinetics study of Fh/BiVO4 by intensity-modulated photocurrent spectroscopy (IMPS) evidences the primary role of Fh on PEC performance enhancement, varying with the loading of Fh. It was found that dispersed Fh nanoparticles accelerate hole transfer for water oxidation, but the resulting photoanode suffers from poor stability. The thick layers of Fh address the stability of the electrode by suppressing surface charge recombination but result in reduced hole transfer rates. Modification of a BiVO4 film with optimally thick layers of discrete nanoflakes effectively reduces charge recombination without compromising stability, leading to a high AM 1.5 G photocurrent of 4.78 mA/cm2 at 1.23 V versus the reversible hydrogen electrode and an applied bias photon to current efficiency of 1.81% at 0.61 V. These values are comparable to the best results reported for undoped BiVO4. (Chemical Equation Presented).

17. Development of metal hydride surface structures for high power NiMH batteries: Also extended cycle-life and lead to more effective recycling methods [2018]

  • Shen, Yang, Noréus, Dag, Professor, and Züttel, Andreas, Professor
Subjects
Natural Sciences, Chemical Sciences, Inorganic Chemistry, Naturvetenskap, Kemi, Oorganisk kemi, Materials Chemistry, Materialkemi, Metal hydrides, NiMH batteries, Surface treatment, Ni clusters, Rare earths hydroxides, Oxygen, Hydrogen, and oorganisk kemi
Abstract
By combining alkaline etching of hydrogen storage alloys or their hydrides with a controlled oxidation, it was possible to improve reaction kinetics and accelerate activation of MH-electrodes. Both AB5 and AB2 alloys were studied where A is mixtures of rare earth elements for AB5 alloys and titanium and/or vanadium, zirconium for AB2 alloys; nickel contributes the major part of B. With SEM and TEM studies the surface could be described as consisting of several phases where an interphase with active Ni-containing cluster protected the inner metallic hydrogen storage part of the powder particles. These catalytic Ni-clusters presumably lead to the fast activation and high discharge capacity of alloy.This interphase was observed to be stable enough to allow us to develop a method, where we could add pure oxygen to a NiMH battery pack in order to regenerate the amount of electrolyte that was lost during long time cycling of the battery. Meanwhile, the method will rebalance the electrodes mitigating excessive pressures during over charge. Therefore, the internal resistance of cells can be reduced and cycle life will increase.It was also shown that the stable interphase could survive a mild ball milling or sonication which enabled us to upcycle material from spent NiMH batteries into a better working MH-electrodes with improved kinetics and activation properties. Reuse of ball-milled or sonicated material could serve as a simple recycling alternative to energy-demanding metallurgical smelting methods and chemical consuming hydrometallurgical recycling processes, where the possibilities of up-scaling further favour the less complex mechanical treatments. The stable but catalytic interphase protecting the inner particles indicates that the MH-electrode material may perform better in its second life in a new NiMH battery.

18. Improved NiMH performance by a surface treatment that creates magnetic Ni-clusters [2016]

  • Shen, Yang, Peng, Fei, Kontos, Sofia, Noreus, Dag, Noréus, Dag, Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik, and Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK)
  • International journal of hydrogen energy. 41(23):9933-9938
Subjects
Natural Sciences, Physical Sciences, Other Physics Topics, Naturvetenskap, Fysik, Annan fysik, Engineering and Technology, Teknik och teknologier, Metal hydrides, NiMH batteries, Surface treatment, Ni clusters, Discharge kinetics, Rare earths hydroxides, Chemical Sciences, Inorganic Chemistry, Kemi, Oorganisk kemi, and oorganisk kemi
Abstract
A surface treatment method has been developed to activate the surface of an AB(5) type (La-20 Ce-7 Pr-1 Nd-4 Al-2 Mn-5 Co-6 Ni-55) alloy. In the process the surface is covered with a porous surface layer containing needle shaped rare earth hydroxides after etching by a potassium hydroxide solution. TEM studies show in addition the presence of a denser surface oxide layer with embedded Ni containing clusters covering the bulk alloy. The magnetic properties of the alloy powders change with the surface treatment. In addition to a paramagnetic component of the bulk alloy, surface treated alloy also displays superparamagnetic and ferromagnetic properties. In electrochemical half-cell tests, the alloy shows better high-rate dischargeability with increasing presence of magnetic clusters in the metal hydride particles surface.

19. Interface manipulation towards wrinkle-free forming of stacked UD prepreg layers [2016]

  • Hallander, P., Sjölander, Jens, Petersson, M., Åkermo, Malin, and KTH, Skolan för teknikvetenskap (SCI), Farkost och flyg, Lättkonstruktioner
  • Composites. Part A, Applied science and manufacturing. 90:340-348
Subjects
Engineering and Technology, Materials Engineering, Teknik och teknologier, Materialteknik, A. Carbon fibre, A. Prepreg, E. Forming, Carbon, Carbon fibers, Friction, Surface treatment, Forming mechanism, Interfacial characteristics, Intraply, Prepregs, and Numerical methods
Abstract
The aim of this paper is to experimentally study how forming behaviour can be changed by local manipulation of prepreg interfacial characteristics. Different methods for surface modification are examined, however all were aimed at enabling significantly increased interply friction. The paper shows that by using increased friction in between layers, these neighbouring pairs will act together during forming, thereby either improving or exacerbating the forming outcome. For the geometry utilized, wrinkle free forming was obtained when the cross-plied layers were paired to deform mainly through intraply shear during forming. The method is supported by the appended numerical analysis and interaction between forming mechanisms and radius thinning is instigated as part of the experimental outcome.

20. Environmental durability of adhesively bonded FRP/steel joints in civil engineering applications: State of the art [2015]

  • Heshmati, Mohsen, Haghani Dogaheh, Reza, and Al-Emrani, Mohammad
  • Composites Part B: Engineering. 81:259-275
Subjects
Samhällsbyggnadsteknik, Civil Engineering, Infrastrukturteknik, Infrastructure Engineering, Fibre reinforced polymer (FRP)/steel joints, Adhesively bonded joints, Laminates, Long term performance, Fibre reinforced polymers, Environmental durability, Surface treatments, Civil engineering applications, Joining, Surface treatment, Fiber reinforced plastics, Debonding, Durability, Polymer Matrix Composites (PMCs), Civil engineering structures, Environmental degradation, Adhesive joints, and Polymer-matrix composites (PMCs)
Abstract
Over the past three decades, the strengthening and repair of existing civil engineering structures using FRP laminates has attracted a great deal of attention. With the advances in polymer science, adhesive bonding has become a common joining technology in these applications. Despite numerous studies that address the short-term behaviour of adhesively bonded FRP/steel joints, uncertainty with respect to long-term performance still remains. This knowledge gap is regarded as a critical barrier, hindering the widespread application of FRPs to strengthen and retrofit steel structures. This paper presents the state of the art in terms of the durability of FRP/steel joints used in civil engineering applications. Important influential factors relating to the durability of adhesively bonded joints are reviewed and different damage mechanisms are discussed. Moreover, related investigations of the combined environmental durability of these joints are critically reviewed and the findings are presented. The paper concludes with a discussion to motivate future research topics, while it is emphasised that the generalisation of the available results is questionable.

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