The Experts below are selected from a list of 37233 Experts worldwide ranked by ideXlab platform
Tom Troczynski - One of the best experts on this subject based on the ideXlab platform.
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Adhesion of thermally sprayed hydroxyapatite-bond-coat systems measured by a novel peel test.
Journal of Materials Science: Materials in Medicine, 1998Co-Authors: H Kurzweg, R. B. Heimann, Tom TroczynskiAbstract:Ti6Al4V foils, 100 μm thick, were coated with thin (10–15 μm) bond coats based on titania and zirconia, and subsequently coated with a thick (100–120 μm) hydroxyapatite layer, using atmospheric plasma spraying. Peel Adhesion Tests of the coating systems performed on the foils showed that titania, and mixed titania/non-stabilized zirconia bond coats improved the Adhesion of the ceramic layers to the metallic substrate in a statistically significant way, while a partially CaO-stabilized zirconia bond coat led to a decrease of the peel Adhesion strength when compared to hydroxyapatite coatings without a bond coat.
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Adhesion of thermally sprayed hydroxyapatite–bond-coat systems measured by a novel peel test
Journal of Materials Science: Materials in Medicine, 1998Co-Authors: H Kurzweg, R. B. Heimann, Tom TroczynskiAbstract:Ti6Al4V foils, 100 μm thick, were coated with thin (10–15 μm) bond coats based on titania and zirconia, and subsequently coated with a thick (100–120 μm) hydroxyapatite layer, using atmospheric plasma spraying. Peel Adhesion Tests of the coating systems performed on the foils showed that titania, and mixed titania/non-stabilized zirconia bond coats improved the Adhesion of the ceramic layers to the metallic substrate in a statistically significant way, while a partially CaO-stabilized zirconia bond coat led to a decrease of the peel Adhesion strength when compared to hydroxyapatite coatings without a bond coat.
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On use of double cantilever beam for coatings and Adhesion Tests
Engineering Fracture Mechanics, 1995Co-Authors: Tom Troczynski, Jean CamireAbstract:Abstract The compliance model of Double Cantilever Beam (DCB) for testing coatings and Adhesion has been proposed and verified experimentally. The model is based on the assumption that the coating modifies the stiffness of a foundation of DCB onto which the beam is fixed, according to a simple series-spring law. The model includes multi-coated specimens, in particular the specimen with thermal sprayed ceramic coating, with an additional layer of epoxy adhesive for attachment of a symmetrical DCB arm. It was found, that the compliance of DCB specimens with a coating is significantly increased for a coating thickness larger than ∼1% of the arm thickness, and a coating Young's modulus smaller than ∼50% of the arm modulus. The model results, verified by experiment, have profound consequences on calculations of the strain energy release rate in fracture Tests for coatings, brazed joints etc. The total compliance of the arm and coating assembly scales with the coating stiffness, and thus the model can be utilised for rigidity evaluation of a variety of coatings on standard substrates, e.g. paints or polymer coatings on metals.
Alisson Rocha Machado - One of the best experts on this subject based on the ideXlab platform.
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Laser texturing of substrate of coated tools — Performance during machining and in Adhesion Tests
Surface & Coatings Technology, 2015Co-Authors: Rhander Viana, Washington Martins Da Silva, Milton Sergio Fernandes De Lima, Wisley Falco Sales, Alisson Rocha MachadoAbstract:Abstract In machining, a laser beam with a high density of energy can be used to promote nano- or microstructural surface changes of the substrate of the tools with the goal of improving the Adhesion of the coatings. The detachment and fragmentation of coatings during machining will compromise tool performance by the premature exposition of the substrate and may cause wear by fragments of hard and abrasive particles. The goal of this study is to test this new technology of laser texturing of cemented carbide inserts of ISO K grade before coating them with TiAlN and AlCrN. The performance of these laser-textured tools was compared with that of microblasted tools (the commercial technique normally used). Tool life Tests in face milling of compacted graphite cast iron (CGI, grade 450) were carried out and the Adhesion of the coated layers to the substrates of the tools was characterized by Rockwell indentation Tests and scratch Tests with a progressive load. The tool life results showed that the laser-textured tools outperformed the microblasted commercial cutting tools under the conditions tested. The Adhesion results measured by scratch and Rockwell indentation Tests showed greater delamination of the microblasted tools than of the laser-textured tools.
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laser texturing of substrate of coated tools performance during machining and in Adhesion Tests
Surface & Coatings Technology, 2015Co-Authors: Rhander Viana, Washington Martins Da Silva, Milton Sergio Fernandes De Lima, Wisley Falco Sales, Alisson Rocha MachadoAbstract:Abstract In machining, a laser beam with a high density of energy can be used to promote nano- or microstructural surface changes of the substrate of the tools with the goal of improving the Adhesion of the coatings. The detachment and fragmentation of coatings during machining will compromise tool performance by the premature exposition of the substrate and may cause wear by fragments of hard and abrasive particles. The goal of this study is to test this new technology of laser texturing of cemented carbide inserts of ISO K grade before coating them with TiAlN and AlCrN. The performance of these laser-textured tools was compared with that of microblasted tools (the commercial technique normally used). Tool life Tests in face milling of compacted graphite cast iron (CGI, grade 450) were carried out and the Adhesion of the coated layers to the substrates of the tools was characterized by Rockwell indentation Tests and scratch Tests with a progressive load. The tool life results showed that the laser-textured tools outperformed the microblasted commercial cutting tools under the conditions tested. The Adhesion results measured by scratch and Rockwell indentation Tests showed greater delamination of the microblasted tools than of the laser-textured tools.
H Kurzweg - One of the best experts on this subject based on the ideXlab platform.
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Adhesion of thermally sprayed hydroxyapatite-bond-coat systems measured by a novel peel test.
Journal of Materials Science: Materials in Medicine, 1998Co-Authors: H Kurzweg, R. B. Heimann, Tom TroczynskiAbstract:Ti6Al4V foils, 100 μm thick, were coated with thin (10–15 μm) bond coats based on titania and zirconia, and subsequently coated with a thick (100–120 μm) hydroxyapatite layer, using atmospheric plasma spraying. Peel Adhesion Tests of the coating systems performed on the foils showed that titania, and mixed titania/non-stabilized zirconia bond coats improved the Adhesion of the ceramic layers to the metallic substrate in a statistically significant way, while a partially CaO-stabilized zirconia bond coat led to a decrease of the peel Adhesion strength when compared to hydroxyapatite coatings without a bond coat.
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Adhesion of thermally sprayed hydroxyapatite–bond-coat systems measured by a novel peel test
Journal of Materials Science: Materials in Medicine, 1998Co-Authors: H Kurzweg, R. B. Heimann, Tom TroczynskiAbstract:Ti6Al4V foils, 100 μm thick, were coated with thin (10–15 μm) bond coats based on titania and zirconia, and subsequently coated with a thick (100–120 μm) hydroxyapatite layer, using atmospheric plasma spraying. Peel Adhesion Tests of the coating systems performed on the foils showed that titania, and mixed titania/non-stabilized zirconia bond coats improved the Adhesion of the ceramic layers to the metallic substrate in a statistically significant way, while a partially CaO-stabilized zirconia bond coat led to a decrease of the peel Adhesion strength when compared to hydroxyapatite coatings without a bond coat.
Rhander Viana - One of the best experts on this subject based on the ideXlab platform.
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Laser texturing of substrate of coated tools — Performance during machining and in Adhesion Tests
Surface & Coatings Technology, 2015Co-Authors: Rhander Viana, Washington Martins Da Silva, Milton Sergio Fernandes De Lima, Wisley Falco Sales, Alisson Rocha MachadoAbstract:Abstract In machining, a laser beam with a high density of energy can be used to promote nano- or microstructural surface changes of the substrate of the tools with the goal of improving the Adhesion of the coatings. The detachment and fragmentation of coatings during machining will compromise tool performance by the premature exposition of the substrate and may cause wear by fragments of hard and abrasive particles. The goal of this study is to test this new technology of laser texturing of cemented carbide inserts of ISO K grade before coating them with TiAlN and AlCrN. The performance of these laser-textured tools was compared with that of microblasted tools (the commercial technique normally used). Tool life Tests in face milling of compacted graphite cast iron (CGI, grade 450) were carried out and the Adhesion of the coated layers to the substrates of the tools was characterized by Rockwell indentation Tests and scratch Tests with a progressive load. The tool life results showed that the laser-textured tools outperformed the microblasted commercial cutting tools under the conditions tested. The Adhesion results measured by scratch and Rockwell indentation Tests showed greater delamination of the microblasted tools than of the laser-textured tools.
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laser texturing of substrate of coated tools performance during machining and in Adhesion Tests
Surface & Coatings Technology, 2015Co-Authors: Rhander Viana, Washington Martins Da Silva, Milton Sergio Fernandes De Lima, Wisley Falco Sales, Alisson Rocha MachadoAbstract:Abstract In machining, a laser beam with a high density of energy can be used to promote nano- or microstructural surface changes of the substrate of the tools with the goal of improving the Adhesion of the coatings. The detachment and fragmentation of coatings during machining will compromise tool performance by the premature exposition of the substrate and may cause wear by fragments of hard and abrasive particles. The goal of this study is to test this new technology of laser texturing of cemented carbide inserts of ISO K grade before coating them with TiAlN and AlCrN. The performance of these laser-textured tools was compared with that of microblasted tools (the commercial technique normally used). Tool life Tests in face milling of compacted graphite cast iron (CGI, grade 450) were carried out and the Adhesion of the coated layers to the substrates of the tools was characterized by Rockwell indentation Tests and scratch Tests with a progressive load. The tool life results showed that the laser-textured tools outperformed the microblasted commercial cutting tools under the conditions tested. The Adhesion results measured by scratch and Rockwell indentation Tests showed greater delamination of the microblasted tools than of the laser-textured tools.
Jian Shen - One of the best experts on this subject based on the ideXlab platform.
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zwitterionic hyperbranched polyester functionalized cardiovascular stent and its biocompatibility
Journal of Colloid and Interface Science, 2014Co-Authors: Xiaobo Wang, Xiaobao Shao, Jingjing Miao, Jian ShenAbstract:Abstract Zwitterionic hyperbranched polyester (HBPE) synthesized on bare metal stents (BMS) surface by surface-initiated atom transfer radical polymerization (SI-ATRP) method. The modified BMS obtained was tested for its blood compatibility. The blood compatibility studies were including, platelet Adhesion Tests, hemolysis assay, morphological changes in RBCs, coagulation Tests, PRT assay, complement activation, platelet activation, and the cytotoxicity was also investigated. The modified BMS surface does not cause platelets adherent, red blood cell disruption, hemolysis and does not induce complement and platelets activation. All results indicated that the modified BMS was blood compatible and no cytotoxicity. It has the potential use for biomedical applications.
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grafting of zwitterion from cellulose membranes via atrp for improving blood compatibility
Biomacromolecules, 2009Co-Authors: Qiang Chen, Shishan Wu, Bo Yuan, Jian ShenAbstract:A p-vinylbenzyl sulfobetaine was grafted from cellulose membrane (CM) using surface-initiated atom transfer radical polymerization for blood compatibility improvement. Surface structure, wettability, morphology, and thermal stability of the CM substrates before and after modification were characterized by attenuated total reflectance Fourier transform infrared spectra, X-ray photoelectron spectroscopy measurement, water contact angle measurement, atomic force microscopy, and thermogravimetric analysis, respectively. The results showed that zwitterionic brushes were successfully fabricated on the CM surfaces, and the content of the grafted layer increased gradually with the polymerization time. The blood compatibility of the CM substrates was evaluated by protein adsorption Tests and platelet Adhesion Tests in vitro. It was found that all the CMs functionalized with zwitterionic brush showed improved resistance to nonspecific protein adsorption and platelet Adhesion, even though the grafting polymerization...
