Digitalization of the thermoplastic beryllium oxide slurry forming process using ultrasonic activation

Abstract

This paper presents the results of the digitalization of the thermoplastic beryllium oxide slurry forming process using ultrasonic activation. Ceramics made from beryllium oxide (BeO) using ultrasound-assisted forming exhibit more intense sintering and, in comparison to ceramics formed without ultrasound, have reduced shrinkage (by 2.4-4.3%) and sintering temperature (by 50-180°C). The forming processes occurring during ultrasonic treatment resulted in the homogenization of the thermoplastic suspension and dense packing of BeO powders in the casting. Ultrasound activation alters the rheology of the thermoplastic slurries. These changes are attributed to processes of slurry mass dispersion and mass exchange at the phase boundary of the suspension. Ultrasound activation also enhances casting properties. During the cooling-solidification process under the influence of ultrasound, the density and strength of the castings increase due to the effective compensation of shrinkage. Shrinkage compensation is carried out according to the classical scheme by supplying a liquid suspension. For hot casting with ultrasound of thermoplastic beryllium oxide slurries, it is advisable to use compositions with a binder content of 11.0-11.7% by weight since these compositions provide better shrinkage compensation and, consequently, a denser casting.