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I would like to make various solid forms of Barium Titanate e.g. cylinders, discs.

Barium Titanate powder seems widely available and has a melting point of 1,625'C. Can I melt it in an iron forge into a mould, and will this preserve the high dielectric constant?

Is there perhaps a low temp way to do this easier e.g. a solvent or additive to achieve the same? Others have tried embedding within epoxy, but with substandard K values (max 27 instead of 7,000 as per the raw powder)

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As you know, barium titanate is a piezoelectric ceramic materials. It has its property as a piezoelectric material due to the specific spatial arrangements of its constituting atoms. Melting this material, means that it will lose its crystalline structure upon heating (knowing also that its Curie Temperature is $T_C=120^o\mathrm{C}$, i.e. above this temperature it loses its ferroelectric property). On the other hand, processing and shaping ceramic materials are often performed during the preparation of these materials, not after. Heating at temperatures around $T_C=1600^o\mathrm{C}$ for processing ceramics is not a common procedure and it is expensive. If you want to prepare cylinders and discs from a powder of barium titanate, you can add it to a polymer matrix (wax, epoxy resin,..) in an appropriate mold using adequate processing techniques like injection molding (heating below Curie Temperature). Of course, the resulting dielectric constant of the composite material is less than the one of pure barium titanate.

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  • $\begingroup$ Are there any matrices you would recommend particularly for a high Bt:matrix ratio? What is the purpose of the heating step in the mold? $\endgroup$ – Nano83 Oct 19 '15 at 9:41
  • $\begingroup$ I recommend epoxy resin, polyester resin or wax. Heating is for cross-linking the thermosets. $\endgroup$ – Yomen Atassi Oct 21 '15 at 14:50

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