Functionally graded materials fabrication

Tokita, M., (2003), Large-size WC/Co functionally graded materials fabricated by spark plasma sintering (SPS) method , Mat. Sci. Forum, 39, 423-425. 

Chemical vapor deposition (CVD) of carbon from propane is the main reaction in the fabrication of the C/C composites [1,2] and the C-SiC functionally graded material [3,4,5]. The carbon deposition rate from propane is high compared with those from other aliphatic hydrocarbons [4]. Propane is rapidly decomposed in the gas phase and various hydrocarbons are formed independently of the film growth in the CVD reactor. The propane concentration distribution is determined by the gas-phase kinetics. The gas-phase reaction model, in addition to the film growth reaction model, is required for the numerical simulation of the CVD reactor for designing and controlling purposes. Therefore, a compact gas-phase reaction model is preferred. The authors proposed the procedure to reduce an elementary reaction model consisting of hundreds of reactions to a compact model objectively [6]. In this study, the procedure is applied to propane pyrolysis for carbon CVD and a compact gas-phase reaction model is built by the proposed procedure and the kinetic parameters are determined from the experimental results. 

Schindler, J., Meyer-Olbersleben, F., Kirbach, B., (1998), Fabrication of FGM-foils for joining application by wet powder spraying , presented at 5th International Symposium on Functionally Graded Materials, Dresden, October 1998. 

Powder pressing is a very flexible process in that materials that are difficult to melt or deform may be produced in a variety of shapes and sizes. Adding to the flexibility of the process may be the fact that the starting powder does not need to be uniform. Different size powders, or more commonly, different types of powders may be used to produce composite microstructures. These different powders may be distributed uniformly throughout the fabricated component, or isolated to form a functionally graded material. Powder pressing is commonly used to... 

C.-W. Hong, F. Muller and P. Greil, Fabrication of Pore-Gradient Membranes via Centrifugal Casting, paper presented at the 4th International Symposium on Functionally Graded Materials (FGM), Tsukuba/Japan, October 20 - 24, 1996. 

Optimum Design and Fabrication of TiC/Ni3Al-Ni Functionally Graded Materials... 

Fabrication of Zr02/Ni and Zr02/Al203 Functionally Graded Materials by Explosive Powder Consolidation Technique... 

Ceramic/metal functionally graded material (FGM) has been developed as a super heat-resistant material used in ultra-high temperature and great temperature gradient environment since 1987 A FGM usually comprises of two or more different material components and has a constitutional gradation over macroscopic distances. The gradual change of constitution between the two sides of FGM can eliminate the traditional joint interface and relax the thermal stress induced by the temperature variation both in fabrication and in service. 

EPD is an efiective technique to synthesize monolithic as well laminates thick film [1-8] and bulk samples [9-13]. Saikar and Nicholson [9,10] are the first to demonstrate the EPD can be successfully use for fabrication of laminated and functionally graded materials. There are few reports on brication of BaTiOj monolithic thick film by EPD [1,5,6]. Yamashita et al [7] is the only one used EPD to synthesize BaTiOj/SrTiO, laminated composite with varying BT/ST ratio and observed board Curie temperature response in the sample. 

Advances in the Fabrication of Functionally Graded Materials using Extrusion Freeform Fabrication... 

Fabrication of Magnetic Functionally Graded Material by Martensitic Transformation Technique... 

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