Synchrotron light sources are large machines, designed to produce the synchrotron light, with the function of unveiling molecular and electronic structures of different materials in order to understand their fundamental properties [1]. These machines operate in ultra-high vacuum atmosphere, requiring specific properties for all the devices used on it, like vacuum tightness, low thermal expansion coefficient, high density and good thermal shock resistance. Silicon carbide (SiC) and aluminum nitride (AlN) are some of the ceramic materials that comply with these properties [2, 3]. Both SiC and AlN are materials that require preferably pressure-assisted sintering process and inert atmosphere to produce dense ceramic components with low or none open porosity, a necessary characteristic to reach adequate vacuum tightness. Hot pressing is the most common technique where pressure is applied along with temperature rise during sintering cycle for industrial purposes [4-7]. In this work ceramic pieces of SiC and AlN were produced by hot pressing at 1900 and 1700 °C, respectively, using Y2O3 as sintering aid. Characterization tests were done in the ceramic parts obtained for identification if the requirements for their application in ultra-high vacuum were achieved.
Acknowledgments:
FAPESP, Finep, Engecer
Reference:
[1] https://www.lnls.cnpem.br/the-lnls/what-is-a-synchrotron-light-source - accessed in 30-04-2019.
[2] https://www.ceramtec.com/ceramic-materials/aluminum-nitride - accessed in 30-04-2019.
[3] https://www.ceramtec.com/ceramic-materials/silicon-carbide - accessed in 30-04-2019.
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