High-Temperature Synthesis of Metal–Matrix Composites (Ni-Ti)-TiB2

Abstract

Currently, metal–matrix composite materials are some of the most promising types of materials, and they combine the advantages of a metal matrix and reinforcing particles/fibres. Within the framework of this article, the high-temperature synthesis of metal–matrix composite materials based on the (Ni-Ti)-TiB2 system was studied. The selected approaches make it possible to obtain composite materials of various compositions without contamination and with a high degree of energy efficiency during production processes. Combustion processes in the samples of a 63.5 wt.% NiB + 36.5 wt.% Ti mixture and the phase composition and structure of the synthesis products were researched. It has been established that the synthesis process in the samples proceeds via the spin combustion mechanism. It has been shown that self-propagating high-temperature synthesis (SHS) powder particles have a composite structure and consist of a Ni-Ti matrix and TiB2 reinforcement inclusions that are uniformly distributed inside it. The inclusion size lies in the range between 0.1 and 4 µm, and the average particle size is 0.57 µm. The obtained metal-matrix composite materials can be used in additive manufacturing technologies as ligatures for heat-resistant alloys, as well as for the synthesis of composites using traditional methods of powder metallurgy.

Synthesis of Metal Matrix Composites Based on CrxNiy-TiN for Additive Technology

“…In addition, it was shown in [33] that chromium nitride decomposes at a temperature of 1770 • C into nitrogen and chromium. Comparing the obtained results with the data from [27,35], it can be assumed that endothermic processes occur in the CrN-TiNi samples through the incongruent melting of the CrN alloy with the evolution of nitrogen and melting of titanium. Then, temperature levelling occurs throughout the entire layer (area 3) and a further temperature decrease takes place, which is characteristic of the cooling of synthesis products.…”

“…In combination with the data presented in [26,27,35], the results obtained from the investigation of the combustion processes in CrN-TiNi samples and the phase composition and structure of the synthesis products allowed us to suggest a mechanism of the formation of the CrNi-TiN composite. Figure 5 presents a diagram of the formation of SHS-produced CrNi-TiN materials in the process of the combustion of the CrN-TiNi powder mixture.…”

“…The apex of the peak corresponds to the system combustion temperature, which is 2000 • C. After the peak, a small decrease in the reaction temperature is observed (area 2), due to the intense heat absorption in the adjacent areas of the initial mixture. Promakhov et al [27] explain this behaviour as the endothermic processes in the reaction zone that are associated with melting components (NiB and Ti). In addition, it was shown in [33] that chromium nitride decomposes at a temperature of 1770 • C into nitrogen and chromium.…”

“…Promakhov et al [27] and Zhukov et al [28] demonstrated the successful production of Al-TiB 2 and (Ni-Ti)-TiB 2 composite materials and found that composites that were obtained by SHS consist of a metallic or intermetallic matrix (Al, Ni-Ti) and ceramic TiB 2 particles whose size varies from 0.1 to 5 µm. At the same time, it was shown by Promakhov et al [27], Zhukov et al [29], and Matveev et al [30] that by changing the composition of the initial mixtures as well as the synthesis conditions, it is possible to control the phase composition and structure of SHS composites, including the size of ceramic inclusions. After being processed, composite powder materials obtained by SHS can be successfully used as raw materials in additive manufacturing machines.…”

Effect of Mechanical Activation of Al-Ti-B Powder Mixture on Phase Composition and Structure of Al-TiB2 Composite Materials Obtained by Self-Propagating High-Temperature Synthesis (SHS)

“…Due to the presence of ceramic inclusions in the metal-matrix composites, their properties (hardness, strength, operating temperatures, and oxidation resistance) are improved relative to traditional metallic materials [ 8 ]. In a previous study [ 9 ], we used the SHS method to obtain composite structured particles from (Ni-Ti)-TiB 2 powders. It was found that the particle structure consisted of an Ni-Ti intermetallic matrix, in which TiB 2 particles were uniformly distributed.…”