Chemical and mechanical tests on the SiO2-ZnO materials for protective coatings of industrial use

ABSTRACT In the Amazon, the sustainable use of wood is associated with technological research that indicates industrial use. Surface roughness of wood is an important criterion for assessing tool condition, machining performance and product quality. The objective of this study was to evaluate the surface roughness of five Amazonian woods used in the manufacture of EGP (Edge Glued Panels).The woods Angelim pedra, Angelim vermelho, Breu vermelho, Murici and Piãozinho, obtained from managed areas of the Amazon, were used in the manufacture of EGP panels. Surface treatments were performed with 120 and 180 grit sandpaper. Surface ripples (roughness) were measured using a digital roughness meter with needle (n = 180 readings). Physical and mechanical tests were performed on both wood and EGP samples, to verify the possible relationship between these properties and roughness. EGP Piãozinho presented better surface quality, which consists of lower roughness (lower surface wave height), while EGP Angelim pedra presented uneven surfaces. Surface quality was satisfactory when 120 grain sandpaper was applied to most products. The results showed a highly significant effect of roughness such as the physical-mechanical properties. The highlight of the study is the wood and EGP Piãozinho, because in all the tests, it always presented the best performances.

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Contribution of Titanium, Chromium and Carbon Buffer Interlayers to Bio-Tribological Properties of Multilayer Composites

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0228 ◽

2016 ◽

Vol 61 (3) ◽

pp. 1391-1398

Author(s):

Ł Major ◽

M. Janusz ◽

J. M. Lackner ◽

B. Major

Keyword(s):

Protective Coatings ◽

Multilayer Coating ◽

Outer Part ◽

Mechanical Tests ◽

Transmission Electron ◽

Multilayer Composites ◽

Before And After ◽

Artificial Vessel ◽

Means Of Transmission ◽

Ball On Disc

Abstract Research studies on bio-tribological protective coatings of titanium, chromium and carbon based have been performed. Thin films were fabricated by hybrid PLD technique (PLD supported by magnetron sputtering). Coatings consisted of two parts; the inner part (first from the substrate) in each case was formed by titanium or chromium/titanium nitride or chromium nitride (Ti/TiN or Cr/Cr2N). The outer part was formed by pure DLC or multilayer DLC/Ti or Cr. No delamination was found at the interface. Titanium or chromium metallic layer was deposited as a first layer directly on the metallic substrate to avoid delamination. All individual layers were built of columnar nano-crystallites. Mechanisms of the mechanical wear of analyzed systems were presented, focusing on the cracking propagation in ball-on-disc tests using an 1 N and 5 N applied loads for 5 000 cycles. Complex microstructure analysis of presented nano-multilayer coatings, before and after mechanical tests, were performed by means of transmission electron microscopy (TEM). The highest stress concentration during mechanical uploading was moved through the multilayer coating by breaking only one layer at the time. The microstructure characterization revealed that cracking propagating in the outer part of the coating was stopped at the interface. In the case of the inner part of the coating Ti/TiN; Cr/Cr2N, ceramic layers showed brittle cracking, while metallic (Ti or Cr) ones deformed plastically. Fabricated coatings were subjected under the analysis in the biomechanical system optimized to test for the direct contact with a human whole blood. The study considered physiological conditions mainly related to the temperature and humidity and the frequency of cyclic deformation of the artificial vessel into which the tested sample was introduced.

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Study of Stability of Al2O3-Y2O3-ZrO2 Composite Ceramics in Crude Petroleum Environment for Inert Coating Applications in Petroleum Industry

Materials Science Forum ◽

10.4028/www.scientific.net/msf.881.318 ◽

2016 ◽

Vol 881 ◽

pp. 318-322

Author(s):

Júlia Oliveira Pontual ◽

Noelle D’emery Gomes Silva ◽

R.A. Sanguinetti Ferreira ◽

Yogendra Prasad Yadava

Keyword(s):

Mechanical Stability ◽

Protective Coatings ◽

Petroleum Industry ◽

Mechanical Tests ◽

Transportation Systems ◽

Composite Ceramics ◽

Crude Petroleum ◽

Chemical Attack ◽

Hardness Tests

Crude petroleum storage and transportation systems suffer from constant physical stress caused by chemical attack of crude petroleum on its structure. Ceramics are materials with high chemical stability in hostile environment and therefore can be used as an inert coating material. In the present work we have produced Al2O3-Y2O3-ZrO2 composites with high mechanical strength, through thermo-mechanical processing. To evaluate the quality of materials developed and the possibility of using them as inert protective coatings, storage and transportation systems, we have studied the physic-chemical and mechanical stability of these materials in crude petroleum originated from onshore and offshore. Structural, microstructural and mechanical tests showed that 15-20wt% ZrO2 composite ceramics with 2 wt% of Y2O3 additives presented better results in terms of mechanical hardness and microstructural characteristics. The study of stability of composite ceramics in crude petroleum environment showed that ceramics did not present any additional phase except the constituent phases. Result of microscopy and Vickers hardness tests also showed that there is no visible change in these characteristics after even 90 days of submersion in crude petroleum. Thus we conclude that composite ceramics could be potential materials for inert coating in crude petroleum environment.

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Oxide Spallation in Beta-NiAl Coated Systems under Mechanicalloading

Materials Science Forum ◽

10.4028/www.scientific.net/msf.595-598.101 ◽

2008 ◽

Vol 595-598 ◽

pp. 101-106 ◽

Cited By ~ 1

Author(s):

Mark Harvey ◽

M. Rambaudon ◽

Vincent Maurel ◽

Luc Rémy

Keyword(s):

Mechanical Load ◽

Protective Coatings ◽

Mechanical Tests ◽

Thermally Grown Oxide ◽

Strain Fields ◽

Thermomechanical Cycling ◽

Oxide Spallation ◽

Damage Field ◽

Damage Extent

Thermally grown oxide (TGO) spallation increases the degradation rate of aluminide protective coatings during thermomechanical cycling. Thermal expansion misfit between TGO, bond coat and substrate, applied mechanical load in the system, and local instabilities are known triggers for spallation. Mechanical tests have been performed on coated and oxidised AM1 superalloy. In situ and post mortem study including digital image analysis and SEM were performed in order to characterise strain fields and associated damage field. Good correlation is found between oxide strain and damage extent.

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Ultrastructure of mesotheliomas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110775 ◽

1984 ◽

Vol 42 ◽

pp. 98-101

Author(s):

Irving Dardick

Keyword(s):

Electron Microscopy ◽

Latent Period ◽

Spindle Cell ◽

Spindle Cell Sarcoma ◽

Metastatic Adenocarcinoma ◽

Cell Sarcoma ◽

Cytological Features ◽

Industrial Use ◽

Degree Of Differentiation

With the extensive industrial use of asbestos in this century and the long latent period (20-50 years) between exposure and tumor presentation, the incidence of malignant mesothelioma is now increasing. Thus, surgical pathologists are more frequently faced with the dilemma of differentiating mesothelioma from metastatic adenocarcinoma and spindle-cell sarcoma involving serosal surfaces. Electron microscopy is amodality useful in clarifying this problem.In utilizing ultrastructural features in the diagnosis of mesothelioma, it is essential to appreciate that the classification of this tumor reflects a variety of morphologic forms of differing biologic behavior (Table 1). Furthermore, with the variable histology and degree of differentiation in mesotheliomas it might be expected that the ultrastructure of such tumors also reflects a range of cytological features. Such is the case.

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Structure-property relationships of PE/PP sandwiched films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126998 ◽

1987 ◽

Vol 45 ◽

pp. 454-455

Author(s):

J. Petermann ◽

G. Broza ◽

U. Rieck ◽

A. Jaballah ◽

A. Kawaguchi

Keyword(s):

Mechanical Tests ◽

Polymer Materials ◽

Ionic Crystals ◽

Structure Property ◽

Polymer Systems ◽

Structure Property Relationships ◽

Oriented Films ◽

Materials Used ◽

Polymer Laminates ◽

Heated Glass

Oriented overgrowth of polymer materials onto ionic crystals is well known and recently it was demonstrated that this epitaxial crystallisation can also occur in polymer/polymer systems, under certain conditions. The morphologies and the resulting physical properties of such systems will be presented, especially the influence of epitaxial interfaces on the adhesion of polymer laminates and the mechanical properties of epitaxially crystallized sandwiched layers.Materials used were polyethylene, PE, Lupolen 6021 DX (HDPE) and 1810 D (LDPE) from BASF AG; polypropylene, PP, (PPN) provided by Höchst AG and polybutene-1, PB-1, Vestolen BT from Chemische Werke Hüls. Thin oriented films were prepared according to the method of Petermann and Gohil, by winding up two different polymer films from two separately heated glass-plates simultaneously with the help of a motor driven cylinder. One double layer was used for TEM investigations, while about 1000 sandwiched layers were taken for mechanical tests.

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Determination of Zr, Y, Gd in zirconium-based targets for magnetron sputtering of thermal protective coatings

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2019-11-68-71 ◽

2019 ◽

pp. 68-71

Author(s):

F.N. Karachevtsev ◽

R.M. Dvoretskov ◽

Е.A. Miheeva

Keyword(s):

Magnetron Sputtering ◽

Protective Coatings

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Effect of silver nitrate on some mechanical properties of heat polymerizing acrylic resins

Mustansiria Dental Journal ◽

10.32828/mdj.v14i1.768 ◽

2019 ◽

Vol 14 (1) ◽

pp. 110

Author(s):

Assiss. Prof. Dr. Sabiha Mahdi Mahdi ◽

Dr. Firas Abd K. Abd K.

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Silver Nitrate ◽

Surface Hardness ◽

Mechanical Tests ◽

Hardness Tester ◽

Acrylic Resins ◽

The Difference

Aim: The aimed study was to evaluate the influence of silver nitrate on surfacehardness and tensile strength of acrylic resins.Materials and methods: A total of 60 specimens were made from heat polymerizingresins. Two mechanical tests were utilized (surface hardness and tensile strength)and 4 experimental groups according to the concentration of silver nitrate used.The specimens without the use of silver nitrate were considered as control. Fortensile strength, all specimens were subjected to force till fracture. For surfacehardness, the specimens were tested via a durometer hardness tester. Allspecimens data were analyzed via ANOVA and Tukey tests.Results: The addition of silver nitrate to acrylic resins reduced significantly thetensile strength. Statistically, highly significant differences were found among allgroups (P≤0.001). Also, the difference between control and experimental groupswas highly significant (P≤0.001). For surface hardness, the silver nitrate improvedthe surface hardness of acrylics. Highly significant differences were statisticallyobserved between control and 900 ppm group (P≤0.001); and among all groups(P≤0.001)with exception that no significant differences between control and150ppm; and between 150ppm and 900ppm groups(P>0.05).Conclusion: The addition of silver nitrate to acrylics reduced significantly the tensilestrength and improved slightly the surface hardness.

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