Sintering Behavior and Microstructure of TiC-Me Composite Powder Prepared by SHS

Abstract

Titanium, its alloys, and refractory compounds are often used in the compositions of surfacing materials. In particular, under the conditions of electron-beam surfacing the use of synthesized composite powder based on titanium carbide with a metal binder (TiC-Me) has a positive effect. These powders have been prepared via the self-propagating high-temperature synthesis (SHS) present in a thermally-inert metal binder. The initial carbide particle distribution changes slightly in the surfacing layer in the high-energy rapid process of electron-beam surfacing. However, these methods also have their limitations. The development of technologies and equipment using low-energy sources is assumed. In this case, the question of the structure formation of composite materials based on titanium carbide remains open, if a low-energy and prolonged impact in additive manufacturing will be used. This work reports the investigation of the sintered powders that were previously synthesized by the layerwise combustion mode of a mixture of titanium, carbon black, and metal binders of various types. The problems of structure formation during vacuum sintering of multi-component powder materials obtained as a result of SHS are considered. The microstructure and dependences of the sintered composites densification on the sintering temperature and the composition of the SH-synthesized powder used are presented. It has been shown that under the conditions of the nonstoichiometric synthesized titanium carbide during subsequently vacuum sintering an additional alloy formation occurs that can lead to a consolidation (shrinkage) or volumetric growth of sintered TiC-Me composite depending on the type of metal matrix used.

Surfacing – Technologies and Layer Properties (A Review)

“…When the aim is to obtain intermetallic compounds with the metal of the substrate in the coating, this can be achieved by adding the second metal in the form of a powder [23]. High cooling rates using heat sources with high energy concentration such as electron beam surfacing (EBS) [25], [26], [27], [28] and [29] or laser surfacing (LS) [30] - [39] creates conditions for modifying the surface layer even without the use of filler materials [25] or after a surfacing process has been performed [3], [26]. The electron beam process is also used for sintering [27] of powder mixture to form layers.…”

“…Electron beam processes are mainly used to improve the properties of the applied layer. Using electron beam scan of the applied layer, the hardness increased 1.7 times and the wear resistance was 70 times higher comparing to substrate [25] and [26]. The main reason for this is the change of structure (a cell structure of 20 ÷ 100μm is obtained) on the surface of the layer due to the high cooling rates.…”

Titanium Alloys 2017

“…A second paper by the authors continues the theme of sintered titanium powders, this time investigating the microstructural evolution of Ti-Al-V-Fe alloys [4]. Titanium-based composites, also produced by a vacuum sintering process, have also found an application in the rapidly developing field of additive manufacturing, and the paper by Korosteleva et al [5] is an interesting investigation into the latest development of these materials. Similarly, titanium boride-based composites as heat insulating materials are an example of a material with a more unique application [6].…”

Ab initio Modelling of Electronic Structure and Mechanical Properties of Substoichiometric TiC$_x$

“…Ãоризонтальними лініями на рис. 4 позначені експериментальні значення модуля всебічного стиснення карбіду титану з різних джерел, починаючи з піонерського експериментального дослідження пружніх властивостей карбіду титану TiC 0,91 [7] та закінчуючи даними електронних баз властивостей керамічних матеріялів (наприклад, [15]); спостерігається добре узгодження з одержаними нами значеннями. Ìодуль всебічного стиснення складових компонентів впливає на твердість/мікротвердість композиційних матеріялів.…”