Influence of technological parameters of centrifugal reinforcement upon quality indicators of parts

Development of the composite material and coatings based on niobium carbide

“…The results obtained are justified by the rational choice of the ceramic component of a composite (NbC) and performing the process at a temperature that makes it possible to receive a pore-free material by providing for wetting capacity. The advantage of the developed composite over those known from [3][4][5][6][7]11] is the simplicity of the technology for obtaining them and a possibility to apply composites in the form of coatings.…”

“…Among them, boron carbide has been investigated [3], in the amount of up to 3 % by weight, when obtaining the composites using the method of solid-phase sintering of the pre-formed billets; higher chromium carbide (Cr 3 C 2 ) [4], in the system of titanium diboride (TiB 2 )copper, under conditions of its reaction thermal synthesis [5]. Paper [6] suggests obtaining the composites that were strengthened with tungsten carbides by applying the method of centrifugal reinforcement, or surfacing [7]. An analysis of results reported in papers [3][4][5][6][7] reveals that a general drawback of composites is their high (~10 %) residual porosity.…”

“…Paper [6] suggests obtaining the composites that were strengthened with tungsten carbides by applying the method of centrifugal reinforcement, or surfacing [7]. An analysis of results reported in papers [3][4][5][6][7] reveals that a general drawback of composites is their high (~10 %) residual porosity. This is predetermined by that such super-hard compounds as B 4 C, TiB 2 , TiC and others, which have been explored lately, are poorly wetted by molten copper at temperatures close to the melting temperature of copper [8].…”

“…However, when applying the method of impregnation, there is an issue related to wetting the refractory phase with a molten. Because the compounds examined in papers [3][4][5][6][7] are poorly wetted by copper, there is a need to find the new refractory compounds for composites with a copper matrix.…”

“…A promising material for obtaining composites with a copper bonding using a method for the impregnation of porous ceramic skeletons with molten is, in particular, niobium monocarbide (NbC), which is well wetted by metals [10] and is characterized by high hardness and chemical stability [11]. Using NbC as a component of composites with a copper matrix, obtained via impregnation, makes it possible to elim-inate the disadvantages characteristic of composites, which were described in papers [3][4][5][6][7]. In other words, to ensure the absence of residual porosity and to increase the content of the carbide phase of up to 60 % by volume.…”