Carbon fiber composites (CFCs) are the first choice as plasma facing materials for the strike poi... more Carbon fiber composites (CFCs) are the first choice as plasma facing materials for the strike points of divertor targets for future nuclear fusion devices like WENDELSTEIN 7-X and ITER. For the application in these facilities several potential European 3D-CFCs were compared and qualified: 1) four material batches of NB31 produced by Snecma Propulsion Solide (SNECMA); 2) NB41, SNECMA, the upgraded version of NB31; 3) N31, SNECMA, which is densified by chemical vapor infiltration (CVI) instead of a final liquid pitch infiltration characteristic for NB31; 4) a new developmental 3D-CFC produced by DUNLOP. The characterization of the composites is comprised of thermo-physical measurements and tensile tests. The results are correlated to density and microstructure and summarized as follows: 1) NB41 provides the highest thermal conductivity in the ex-pitch direction of ~375 W/m.K at room temperature; 2) all material grades are, due to their heterogeneity, characterized by a relatively large scatter of mechanical properties; 3) the different densification process for N31 in comparison to NB31 has no influence on the material properties; 4) NB41 provides in all 3 directions a comparably high tensile strength with an average in the ex-pitch direction of ~220 MPa; 5) the 3D-
In Africa, several techniques have been used depending on the region for the construction of habi... more In Africa, several techniques have been used depending on the region for the construction of habitats. Modern buildings with excessive energy consumption are very costly for developing countries and cause environmental degradation. At Chad, pod of wheat and cow dung are the two main traditional materials mixed with clay for the construction of housing. However, the characteristics of these materials are still unknown. This is why we studied the thermal characteristics of clay-based brick and wheat pod. Clay of the Site of Madagua (in N'Djamena) that we used was dug to a depth of 1.5 m and sieved at 80 microns diameter. The results show that the studied materials are environmentally friendly and can improve the thermal efficiency of buildings.
IOP Conference Series: Materials Science and Engineering, 2017
This work is part of the valuation of local materials such as clay (earth), alfa fiber and straw ... more This work is part of the valuation of local materials such as clay (earth), alfa fiber and straw fiber. The goal is to use these materials as bricks in rural construction. These materials are abundant, natural, and renewable. The objective of this work is to study the thermal and mechanical behavior of a new material by mixing clay (chosen as the binder) with different mass percentages of alfa fiber (0.5%, 1%, 2%, 3%, 4%), and to compare these results with those of materials often used in the construction of individual houses in rural Morocco (clay + straw). The results obtained prove to us that using straw fibers can reduce the thermal conductivity compared to alfa fiber, which allows to have energy savings of 2% to 7%. By against, alfa fibers can improve the mechanical behavior of clay-based materials when compared to the clay + straw material (an increase of 8% to 17% in the tractive resistance by bending and 6% to 18% for compression resistance). These results also specify the optimal usage conditions of these fibers (alfa and straw) in the clay bricks.
Research Journal of Applied Sciences, Engineering and Technology, 2015
Clay and alfa fiber are abounding, natural and renewable materials, they have thermal and acousti... more Clay and alfa fiber are abounding, natural and renewable materials, they have thermal and acoustical ownership very interesting. In the present job, we studied the thermal behavior of the different samples of dimensions 10×10×3 cm 3 by blending Clay with a different percentages of fibers alfa (0.5, 1, 2, 3 and 4%, respectively). Then we compare thermal ownership of this new materials (clay+alfa) with the only Clay to valorize the addition of fibers alfa and her use with Clay as insulating material. Results point out that the new composite material is lighter and less effusive, its capacity to delay the transmission of warmth is superior to that of the only clay and its use as outside wall should give an energy saving over 30%.
This work is part of the development of local materials such as clay and fiber alfa in the north ... more This work is part of the development of local materials such as clay and fiber alfa in the north of Morocco. These materials are abounding, natural and renewable, they have thermal properties very interesting. Our objective is to study the fiber alfa effect on the thermal characteristics of clay based materials. For this reason we mix the clay (chosen as base material) with different percentages of fibers alfa (0.5%, 1%, 2%, 3%, 4%).Then we compare the properties thermo physical of this new material with those of clay only, to motivate the proposal to use this material as insulation in rural construction. This comparison of the energy performance of these two materials will enable us to deduce that the new material is less effusif than clay alone, its lightness exceeds that of clay only, and its use as brick walls should give an energy saving over 30%.
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