## 1 Introduction  
Over the last few years, there has been increasing interest in the exploration of production methods for nanostructured materials because their physical properties change as the crystallite particle size decreases. There are new features in the electronic structure at nanosized scales, which are sensitive to the properties of the materials' constituent elements. The presence of carbon yields excellent mechanical and catalytic properties, mainly when the carbon is mixed or used to support transition metals [1; 2; 3]. An example of these kinds of materials is NiW, MoW, and NiMoW phases, which have attracted attention by the petrochemical industry due to their applications as catalysts in extra-heavy desulfurization crudes. These systems are cheaper than other catalysts for the same purpose [4]. Previous research showed that MoW and NiW systems combined with carbon to produce carbides and compounds compete against other mechanically reinforced materials by adding elements like Al\({}_{2}\)O\({}_{3}\) and ZrO\({}_{2}\) composites; even their performance is comparable to multiwall carbon nanotubes (MWCNTs) [5; 6; 7; 8; 9]. Another advantage of these materials is that the formation of bulk materials from transition metal carbide powders is feasible since sintering performs under friendly conditions [10]. Besides, currently, Mo- and W-based materials are being analyzed as dielectrics with good capacity for storage and processing of thermal and electrical energy [10]. Only a few studies in the literature analyzed the formation and microstructural evolution of the MoW phase as an alloy and the transformation of bimetallic carbides of those metals, such as the change from MoW to MoWC. This condition is because the synthesis methods are costly or involve chemical reactions at very high temperatures [7; 11; 12; 13; 14]. However, this situation has changed since new production methods are now available. For example, [PERSON] et al. reported a MoW solid solution with polycrystalline single-phase microstructure produced by mechanosynthesis, but the authors did not mention the resultant crystalline structure produced after the solid solution during mechanical alloying (MA) [15]. Later [PERSON] et al. synthesized nanocrystalline W-based powder particles; their results showed that with mechanical milling, they increased high-density crystalline defects that make them suitable as alloys in systems that are complicated to produce by other conventional synthesis methods [10]. Mechanical alloying (MA) is a solid-state technique involving repeated particle fracture that can be processed through high- or low-energy ball mills. It is a versatile and low-cost process for synthesizing super-saturated phase nanopowders, solid solutions, nanocrystalline materials, and immiscible systems [16; 17]. For example, a recent study by [PERSON] et al. found the formation of a solid solution in a full range of compositions by the sol-gel method combined with hydrogen reduction [11]. The MA method has the advantage that it can produce a powder with nanoscale particles in large quantities compared with other methods like the sol-gel [3; 18; 19]. These findings demonstrate that MA may be a useful approach in producing nanostructured carbides, making them optimal for heavy crude oil desulfurization applications during catalytic aqua-thermolysis [20]. Other studies report MoWC phase production only in a hexagonal crystalline structure at high pressure or temperature [21; 22]. However, there are no reports about the production of MoWC alloys with a bcc crystalline structure even when Haag rules predict their existence [23]. Hence, additional work is necessary to understand the phase transformation from Mo and W to MoW and MoWC.