Gradient structure materials

Although the functionally graded materials concept has been known since 1972, the production of functionally graded SiAlON ceramics is still a subject to explore. Especially, the formation mechanisms of the functional gradient structure have not yet been fully understood. If diffusion mechanisms are explored, compositional design would be easy and the thickness of the graded... 

The Society ofNon-traditional Technology, Development of Energy Conversion Materials through Formation of Gradient Structures, (1994). 

Barabash, O.M., Milman, Yu.V., Voskoboinik, I.V., Korzhova, N.P. and Legkaya, T.N. (2001) Structure and Physical-Mechanical Properties of Gradient Eutectic Materials Al-Mg2Si (GE), Functional Materials 8, No.l, 159-161. 

The structural materials that conform the cantilevers can have intrinsic stresses and stress gradients because of the fabrication processes. These can change the mechanical performance of the microcantilevers. If stresses and stress gradients are high, they must be previously measured by using specific test structures and their values should be included in the simulations. As monocrystalline silicon will be used in the fabrication of our devices, these stresses can be neglected. 

Characterization of Compositional Gradient Structure of Polymeric Materials by FTIR Technology... 

Fig. 184. Possible modes of polar differentiation. (A) Polar field polarity a concentration of different materials at the poles of the cell. (B) Structural, directional polarity polar directed structures pass through the interiors and/or around the periphery. (C) Gradient polarity material gradients between the poles (from Kuhn 1965).

A gradient polymeric material may also be obtained by a specific treatment of a polymeric beam waveguide surface. Thus, for example, processing of an optical fiber consisting of the core and the cover (PMMA), by a low-molecular alcohol leads to a decrease of refractive index by diffusion of the low-molecular compound and breach of the cover structure [2]. 

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