Einfluss verschiedener Substratwerkstoffe auf Struktur und Eigenschaften anodischer Oxidschichten aus Oxalsäure. The influence of substrate material on structure and properties of anodic oxide coatings from oxalic acid

The kinetic parameters of the reaction steps of the oscillation cycle and the parameters of modified oscillation reactions of the Belousov-Zhabotinskii (BZ) type with oxalic acid, tartaric acid, and hypophosphite ions were compared with predictions of Edelson's analysis based on the mechanism of the classical BZ reaction.

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THE EFFECT OF ELECTROLYTE TEMPERATURE AND SEALING SOLUTION IN ANODIZING OPERATION ON HARDNESS AND WEAR BEHAVIOR OF 7075 -T6 ALUMINUM ALLOY

Surface Review and Letters ◽

10.1142/s0218625x18501433 ◽

2019 ◽

Vol 26 (02) ◽

pp. 1850143

Author(s):

SAEED NIYAZBAKHSH ◽

KAMRAN AMINI ◽

FARHAD GHARAVI

Keyword(s):

Weight Loss ◽

Wear Resistance ◽

Aluminum Alloy ◽

Wear Behavior ◽

Anodic Oxide ◽

Boiling Water ◽

Electrolyte Temperature ◽

Oxide Coatings ◽

Sodium Dichromate ◽

Pin On Disk

Anodic oxide coatings are applied on aluminum alloys in order to improve corrosion resistance and to increase hardness and wear resistance. In the current study, a hard anodic coating was applied on AA7075-T6 aluminum alloy. To survey the anodizing temperature (electrolyte temperature) effect, three temperatures, namely, [Formula: see text]C, 0∘C and 5∘C were chosen and the samples were sealed in boiling water and sodium dichromate to study the role of sealing. For measuring the oxide coatings porosity and hardness and also for comparing the samples’ wear resistance field-emission scanning electron microscopy (FESEM), microhardness test and pin-on-disk method were utilized, respectively. The results showed that by increasing the anodizing temperature, hardness and consequently wear resistance decreased so that hardness and weight loss in the samples with no sealing decreased from 460[Formula: see text]HV and 0.61[Formula: see text]mg at [Formula: see text]C to 405 and 358[Formula: see text]HV and 1.05 and 1.12[Formula: see text]mg at 0∘C and 5∘C, respectively, which is due to the porosity increment by increasing the anodizing temperature. Also, sealing in boiling water and dichromate contributed to soft phases and coating hydration, which resulted in a decrease in hardness and wear resistance. Hardness and weight loss in the coated samples at [Formula: see text]C decreased from 460[Formula: see text]HV and 0.61[Formula: see text]mg in the samples with no sealing to 435 and 417[Formula: see text]HV and 0.72 and 0.83[Formula: see text]mg in the samples sealed in boiling water and dichromate, respectively.

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High photocatalytic activity of TiO2 thin films on the electrolytically colored anodic oxide coatings of aluminum

Journal of Japan Institute of Light Metals ◽

10.2464/jilm.53.410 ◽

2003 ◽

Vol 53 (10) ◽

pp. 410-415 ◽

Cited By ~ 4

Author(s):

Takayoshi FUJINO ◽

Takuya NARA

Keyword(s):

Thin Films ◽

Photocatalytic Activity ◽

Anodic Oxide ◽

High Photocatalytic Activity ◽

Oxide Coatings ◽

Tio2 Thin Films

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Influence of Substrate Materials on Nucleation and Properties of Iridium Thin Films Grown by ALD

Coatings ◽

10.3390/coatings11020173 ◽

2021 ◽

Vol 11 (2) ◽

pp. 173

Author(s):

Paul Schmitt ◽

Vivek Beladiya ◽

Nadja Felde ◽

Pallabi Paul ◽

Felix Otto ◽

...

Keyword(s):

Thin Films ◽

Film Growth ◽

Bulk Material ◽

Atomic Layer ◽

Substrate Material ◽

Fused Silica ◽

Silicon Wafers ◽

Force Microscopy ◽

Angle Measurements ◽

Influence Of Substrate

Ultra-thin metallic films are widely applied in optics and microelectronics. However, their properties differ significantly from the bulk material and depend on the substrate material. The nucleation, film growth, and layer properties of atomic layer deposited (ALD) iridium thin films are evaluated on silicon wafers, BK7, fused silica, SiO2, TiO2, Ta2O5, Al2O3, HfO2, Ru, Cr, Mo, and graphite to understand the influence of various substrate materials. This comprehensive study was carried out using scanning electron and atomic force microscopy, X-ray reflectivity and diffraction, four-point probe resistivity and contact angle measurements, tape tests, and Auger electron spectroscopy. Within few ALD cycles, iridium islands occur on all substrates. Nevertheless, their size, shape, and distribution depend on the substrate. Ultra-thin (almost) closed Ir layers grow on a Ta2O5 seed layer after 100 cycles corresponding to about 5 nm film thickness. In contrast, the growth on Al2O3 and HfO2 is strongly inhibited. The iridium growth on silicon wafers is overall linear. On BK7, fused silica, SiO2, TiO2, Ta2O5, Ru, Cr, and graphite, three different growth regimes are distinguishable. The surface free energy of the substrates correlates with their iridium nucleation delay. Our work, therefore, demonstrates that substrates can significantly tailor the properties of ultra-thin films.

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Influence of Substrate Material on Flow in Freezing Water Droplets—An Experimental Study

Water ◽

10.3390/w13121628 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1628

Author(s):

Erik Fagerström ◽

Anna-Lena Ljung ◽

Linn Karlsson ◽

Henrik Lycksam

Keyword(s):

Turbine Blades ◽

Maximum Velocity ◽

Substrate Material ◽

The Arctic ◽

Natural Phenomenon ◽

Contact Radius ◽

Freezing Process ◽

Water Droplets ◽

Symmetry Line ◽

Influence Of Substrate

Freezing water droplets are a natural phenomenon that occurs regularly in the Arctic climate. It affects areas such as aircrafts, wind turbine blades and roads, where it can be a safety issue. To further scrutinize the freezing process, the main objective of this paper is to experimentally examine the influence of substrate material on the internal flow of a water droplet. The secondary goal is to reduce uncertainties in the freezing process by decreasing the randomness of the droplet size and form by introducing a groove in the substrate material. Copper, aluminium and steel was chosen due to their differences in thermal conductivities. Measurements were performed with Particle Image Velociometry (PIV) to be able to analyse the velocity field inside the droplet during the freezing process. During the investigation for the secondary goal, it could be seen that by introducing a groove in the substrate material, the contact radius could be controlled with a standard deviation of 0.85%. For the main objective, the velocity profile was investigated during different stages of the freezing process. Five points along the symmetry line of the droplet were compared and copper, which also has the highest thermal conductivity, showed the highest internal velocity. The difference between aluminium and steel was in their turn more difficult to distinguish, since the maximum velocity switched between the two materials along the symmetry line.

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