Thermal spraying of polymers

Petrovicova, E.; Schadler, Linda S.

doi:10.1179/095066002225006566

Cited by 87 publications

(55 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Some characteristics of the coating powder, mainly the chemical composition, morphology, molar mass, and particle size, must be adapted to the spraying process parameters and variables. In particular, these include 1) feedstock variables: powder type, size, and shape, carrier gas flow and velocity; 2) torch variables: power, type of thermal energy, gas flow, temperature, cooling; 3) jet variables: jet exit velocity and temperature, particle velocity and temperature, particle trajectory; and 4) substrate variables: type and temperature 1 . Zhang et al 5,6 reported that the spraying parameters have significant effects on the heating, melting, and degradation of the particles …”

Section: Introductionmentioning

confidence: 99%

“…Thermal-sprayed polymer coatings have gained significant attention from many industries, including the petrochemical, automotive, and aircraft industries. They have been used in surface protection against humidity, corrosion, and aggressive chemical products 1 . One of the greatest advantages of thermal spraying compared to other coating techniques is that the coatings can be applied and repaired in the field, and application is not restricted by the size of the surface to be coated 1 .…”

Section: Introductionmentioning

confidence: 99%

“…They have been used in surface protection against humidity, corrosion, and aggressive chemical products 1 . One of the greatest advantages of thermal spraying compared to other coating techniques is that the coatings can be applied and repaired in the field, and application is not restricted by the size of the surface to be coated 1 . Polymeric materials are expected to be used in corrosion and wear protection with economic advantages over the currently available alternatives 2 .…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Wear, friction, and microhardness of a thermal sprayed PET: poly (ethylene terephthalate) coating

et al. 2009

View full text Add to dashboard Cite

The effects of combustion thermal spraying parameters namely combustion pressure, feeding rate, and carrier gas on the wear resistance, friction coefficient, and Knoop hardness of poly (ethylene terephthalate) (PET) films were investigated. The PET coatings were characterized by measuring the wear coefficients by calowear-type testing, the friction coefficients by a pin-on-disk test, and Knoop hardness. The abrasive wear and friction coefficients of the coatings were compared with the values of a post consumer PET bottle chip reference sample. The structural characteristics of the coatings were investigated by X ray diffraction. Statistical analysis of the results allowed for the systematic characterization of the influence of the process variables mentioned above on the coating wear, friction, and microhardness values. Specifically, this study shows that the process parameters affect the wear coefficient and Knoop hardness significantly, but not the friction coefficient. The degree of crystallinity of the PET coatings varied from 20 to 26%. Keywords: thermal spray, PET, tribology*e-mail: rogerioxavier@yahoo.com.br, jose.branco@cetec.br, vilmaccosta@hotmail.com, calado@eq.ufrj.br 122 Nunes et al. Materials Researchparameters were 10 rpm, 14 mm trail diameter, 10-N load, 50 turns, and a traveled distance of 2,200 mm. Each sample was measured in triplicate. The samples were weighed before and after testing for calculation of mass loss. Wear testAbrasive wear was evaluated by calowear testing, which involves the interaction of a rotating steel sphere with the sample surface with alumina as an abrasive. A semi-spherical crater was formed on the contact surface of the sample. The wear rate was calculated from the crater dimension using Equations 2, 3, and 4:where D is the crater diameter, n the number of turns, R the sphere radius, V the lost volume, S the sliding distance, and Q the wear rate 12 .The wear coefficient (K) was calculated with the Archad equation 10 , where W is the applied load and H the hardness.The sliding distances of the sphere were 100, 200, 300, 500, and 1000 turns and the applied load was 13.7 N. Each sample was measured in triplicate. The crater diameter was measured by 3D profilometry. Results and Discussion Coating structureUsing an optical microscope, the presence of bubbles or pores at the substrate/coating interface and in the PET coating medium was not observed. However, they were observed on the coating-free surface. The formation of bubbles is explained in the following way. The final coating temperature was around 410 °C, below the degradation temperature of PET (420 °C). Apparently, the temperature reached by the deposited layers was sufficient for their complete coalescence between the substrate and the coating medium. Particle degradation was insignificant. This will be further discussed with the results of the infrared spectroscopy. Due to the heterogeneous size of the PET particles, the smallest ones probably melted, while the larger ones were semi-melted. During the natural cool...

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Wear, friction, and microhardness of a thermal sprayed PET: poly (ethylene terephthalate) coating

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Dentre os parâmetros do processo ou suas variáveis destacam-se: 1) variáveis de alimentação: tipo, tamanho e forma do pó; fluxo e velocidade do gás de arraste; 2) variáveis da tocha: fluxo e composição dos gases; temperatura da tocha; resfriamento; energia térmica; 3) variáveis da aspersão: velocidade e temperatura das partículas; trajetória das partículas até a tocha; energia e ângulo de impacto; estado de solidificação; morfologia; e 4) variáveis do substrato: tipo e temperatura; distância de aspersão [5] .…”

unclassified

Atrito e desgaste de recobrimentos de PET, politeraftalato de etileno, pós-consumo processados por aspersão térmica

2007

View full text Add to dashboard Cite

Resumo: A aspersão térmica envolve processos de recobrimentos que podem utilizar materiais cerâmicos, poliméricos, metálicos ou misturas destes. O material a ser depositado é fundido total ou parcialmente. As partículas aquecidas são aceleradas e projetadas em direção a uma superfície devidamente preparada, onde se formam camadas com estrutura lamelar. Os efeitos das variáveis do processo de aspersão, pressão dos gases de combustão, taxa de alimentação e gás de arraste no transporte do material, sobre a resistência ao desgaste e atrito de filmes PET foram investigados. Os recobrimentos de PET foram caracterizados através do desgaste micro-abrasivo, utilizando o ensaio de caloteste, e da medida dos coeficientes de atrito, com o ensaio de pino-sobre-disco. Os valores do coeficiente de desgaste abrasivo e do coeficiente de atrito dos recobrimentos são comparados com os valores da garrafa PET utilizada como referência. Os coeficientes de desgaste encontrados foram similares aos valores de garrafas PET da ordem de 10 -5 . As análises estatísticas dos resultados deste trabalho indicam que os efeitos das interações das três variáveis, pressão dos gases de combustão, taxa de alimentação e gás de arraste foram significativos para o coeficiente de desgaste e não significativos para o coeficiente de atrito. Palavras-chave: Aspersão térmica, PET, tribologia. Friction and Wear of a Thermal Sprayed PET -Poly(Ethylene Teraphthalate) CoatingAbstract: The thermal spray technique involves coating processes that can use ceramic, polymers, metallic materials or a blend of these. The material to be deposited is melted totally or partially, where the heated particles are accelerated and projected toward a prepared surface forming layers with a lamellar structure. The effect of the spray process parameters such as, combustion pressure, feed rate and carrier gas, on the wear resistance and friction of PET films was evaluated. The PET coatings were characterized by measuring the wear coefficient through the calowear type testing and the friction coefficients using pin-on-disk testing. The values of the abrasive wear coefficient and the friction coefficient of the coatings were compared to the values of the bottle PET reference sample. The wear coefficient values were similar to the values for the PET bottles, in the range of 10 -5 . The statistical analyses of the results indicate that the interaction effects of the three variables, gas pressure, feeding rate and carrier gas were significant for the wear coefficient but not for the friction coefficient. Keywords: Thermal spray, PET, tribology. IntroduçãoA técnica da aspersão térmica, dentro da Engenharia de Superfícies, mantém-se como uma das suas promissoras alternativas para a produção de novos materiais com características para atender as crescentes exigências do mercado em relação às suas propriedades físicas, químicas e tribológicas.O papel da aspersão térmica no avanço tecnológico tem experimentado reconhecimento crescente. A aspersão tér-mica é um processo que foi usado inicialme...

show abstract

“…In particular, flame spraying allows melting and forming a layer in a single operation. Since 1970s, guns of "oxygen/air -acetylene/propane combustion mixtures are used for flame spraying of polymer materials [1][2][3][4]. The guns are able to spray polymer powder coatings from polyvinyl butyral, polyamide, [5][6][7].…”

Section: Introductionmentioning

confidence: 99%