Abstracts Book - IMRC 2018

• SF7-P003
SYNTHESIS OF RADIOABSORBING CERAMICS BASED ON SILICON
CARBIDE AND TUSINE
Irina Nikolaenko 1 , Cvetlana Antipina 2 , Efraín Rubio Rosas 3
1 Institute of Solid State Chemistry, the Ural Branch of the Russian Academy of Sciences, Russia.
2 Yeltsin Ural Federal University, , Russia. 3 Benemerita Universidad Autonoma de Puebla,
Centro Universitario de Vinculación y Transferencia de Tecnología, Mexico.
A new composite material with improved dielectric, electrothermal and
absorbing properties has been synthesized by introducing a promising dopant
into a silicon carbide based ceramic matrix and by optimizing its chemical
composition as a result of studying of the thermophysical and other
characteristics. A new material “tusine” was chosen as a dopant, which is a
heterogeneous mixture of titanium carbonitride and silicon carbide obtained by
reduction of leucoxene concentrate in a nitrogen stream. Materials based on
tusine have good wear resistance, chemical resistance, and high
thermomechanical parameters, which allows using it for the synthesis of radioabsorbing
ceramics working in oxidizing and reducing environments. The
investigations into the dielectric and thermomechanical properties revealed that
the best composition contains 10 wt. % tusine and has the maximum heating
temperature 1300 ° C for 5-10 min. On the basis of this composition we have
synthesized a radio-absorbing ceramics with dielectric permittivity e = 4.65 and
a dielectric loss tangent tg d = 0.082. Optimal thermomechanical (50 thermal
changes) and strength characteristics (hardness 55 HRA, porosity 27.4 % and
water absorption 9.4 %) were obtained on pressed samples at a pressure of 100
MPa. The chemical analysis data show that during processing of ceramics with
inorganic acids, mainly iron and partly aluminum are extracted into the liquid
phase the impurity phases - iron and aluminum oxides and iron silicide. The
main components - silicon and titanium - are hardly extracted into solutions of
inorganic acids. In this paper we show how a small amount of dopant allows to
accumulate heat, conserve energy and increase the thermomechanical
characteristics of radioabsorbing ceramics.
Keywords: Radio-absorbing ceramics, Silicon carbide, Tusine
Presenting authors email: nikolaenko@ihim.uran.ru