Mechanical Engineering for Society and Industry

Diamond-metal matrix composites (DMMC) exhibit exceptional hardness, thermal conductivity, and wear resistance, making them highly appealing for a range of industrial applications. Current production methods operate at elevated temperatures, which pose risks of metal phase transformation and inadequate wettability. This work examined the structure and properties of a diamond-reinforced titanium matrix composite synthesized by self-propagating high-temperature synthesis (SHS). The materials were prepared using Ni, Al, Ti, and C, with a high Ti content. The combustion synthesis was initiated by induction heating at 3 kW. The reaction temperature was monitored using an infrared thermometer. The product’s morphology was characterized using Scanning Electron Microscopy, X-ray diffraction, and Raman spectroscopy. The mechanical properties of the product were evaluated using Vickers hardness testing. The results demonstrate that the ignition point is delayed, attributed to the high Ti composition. An increased C fraction in the mixture delays ignition. All samples, however, achieve the same maximum combustion temperature of approximately 1800 °C. The high combustion temperature of the SHS reaction can transform Ni, Al, Ti, and C materials into new products, including carbides and intermetallics such as TiC, Ti₄Ni₂C, Al₄O₄C, and diamond. These particles are the composite reinforcement, which is dispersed in the Ti matrix. The hardness reaches its highest value of 870.1 ± 20.4 HV in the sample prepared with 0.024 g of C. The present finding provides a deeper understanding of the production of diamond-metal matrix composites through an alternative, simple, and lower-cost process: self-propagating high-temperature synthesis.