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Fabrication of Cu-Based SiC Composites by Spark Plasma Sintering of Cu-Nitrate Coated SiC Powders

Jeong Y.-K., Kim Y. S., Oh S.-T.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1407--1410

EN

An optimum route to fabricate the Cu-based SiC composites with homogeneous microstructure was investigated. Three methods for developing the densified composites with sound interface between Cu and SiC were compared on the basis of the resulting microstructures. Starting with three powder mixtures of elemental Cu and SiC, elemental Cu and PCS coated SiC or PCS and Cunitrate coated SiC was used to obtain Cu-based SiC composites. SEM analysis revealed that the composite fabricated by spark plasma sintering using elemental SiC and Cu powder mixture showed inhomogeneous microstructure. Conversely, dense microstructure with sound interface was observed in the sintered composites using powder mixture of pre-coated PCS and Cu-nitrate onto SiC. The relationship between powder processing and microstructure was discussed based on the role of coating layer for the wettability.

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Hypothetical fracture at fibber-matrix interface in Cu-SiC composite due to thermal stresses

Czarnocki P., Krzesiński G., Marek P., Zagrajek T.

Archive of Mechanical Engineering

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2008

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Vol. LV, nr 1

57-66

EN

The Copper-SiC composite was investigated with the help of FEM. The authors modeled and analyzed the effect of relaxation of thermal stresses due to seasoning at room temperature after the manufacturing process together with the effect of thermal stresses induced by reheating the material to a service temperature. Especially, hypothetical fracture at interface was of interest. It was shown that, for a fixed temperature, a single crack emanating at 0° or 45° azimuth would develop only along a portion of fiber perimeter, and a further growth would require stress increase in the fiber surrounding.

PL

W pracy analizowano stan naprężeń cieplnych w kompozycie Cu-SiC, wynikających ze spadku temperatury od temperatury wytwarzania do temperatury pokojowej oraz relaksacji naprężeń w okresie sezonowania w tej temperaturze a następnie podgrzaniu kompozytu do temperatury przewidywanej pracy. Szczególną uwagę zwrócono na możliwości rozwoju pęknięć na granicy włókna i spoiwa w temperaturze pracy. Rozpatrywano dwie lokalizacje 0 i 45 stopni. Stwierdzono, iż w obu przypadkach, w ustalonej temperaturze hipotetyczna propagacja pęknięć będzie stabilna w tym sensie, iż rozwiną się one jedynie na pewnej długości obwodu włókna a ewentualny dalszy ich rozwój będzie wymagał wzrostu naprężeń w jego otoczeniu.

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Finite element method modelling of the properties of a Cu-SiC composite under cyclic loading conditions

Miśkiewicz M. A., Matysiak H., Kurzydłowski K. J.

Materials Science Poland

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2007

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Vol. 25, No. 3

687--697

EN

The paper reports on finite element method (FEM) analysis of Cu-SiC composites behaviour under cyclic loading conditions. In order to emphasise the influence of materials description on following results, there were two hardening rules used to describe the plastic behaviour of the matrix: (a) simple isotropic and (b) combined isotropic-kinematic. Reinforcing ceramics was assumed to be perfectly elastic. The analysis was carried out for Cu-SiC fibre-reinforced lamina composite. The fibre volume fracture was assumed to be 20%. The modelling was based on representative volume element (RVE) geometry. Additionally, the effect of thermal residual stresses was taken into account and its influence upon the Cu-SiC composite mechanical behaviour was clarified.