3D printing of heaters based on MoSi2 by Robocasting method

Abstract

One of the main directions of 3D printing is obtaining products of complex shapes to replace worn or damaged analogues. Modern analytical equipment for heat treatment of materials is produced in small batches and contains heating elements of complex shapes. Replacing these heating elements is an expensive and complicated process. Using modern 3D printing technologies, such as the Robocasting method, it is possible to print products of complex shapes from a material similar to that used in the device, or even better, [1,2]. In our work, we investigated the process of manufacturing heaters of complex shapes based on MoSi2, from the preparation of pastes for 3D printing using the Robocasting method to their consolidation and determination of the characteristics of the obtained heating elements. The shapes of the heating elements were obtained using the Robocasting method. This involved employing layer-by-layer printing on the Ender 5 printer with the Stoneflower 2 ceramic module and using a paste based on MoSi2 powder. A study of the rheological properties of pastes based on molybdenum disilicide and synthetic rubber with gasoline as a binder was conducted. It was established that the print scale (nozzle/filament diameter) depends on the content of the plasticizer. The smaller the nozzle, the greater the content of plasticizer required to obtain a high-quality product shape closest to a digital twin. Several samples of different forms were printed using Robocasting technique. Printed forms were heat-treated in a vacuum drying chamber at a temperature of 400° for 2 hours. Sintering was carried out in the high temperature vacuum furnace at 1900°C, holding time - 1 hour. After sintering, the residual porosity of the samples is 15-17%. The Vickers hardness of the samples was 9.5±1.4 GPa. When determining the current-voltage characteristic, the heater was heated to a temperature of about 90°C at a power of 1 W.