Microstructure and Wear Analysis of Copper-Graphite-Titanium Carbide Hybrid Metal Matrix Composites Fabricated by Powder Metallurgy (P/M) Technique

Abstract

In the present paper, powder metallurgy (P/M) was employed to create copper matrix composites reinforced with Graphite (Gr.)-Titanium Carbide (TiC) [at 5, 10, and 15 wt. %]. Both Gr. and TiC was used in equal concentration as reinforcements. For this experiment, cylindrical specimens with approximate dimension of 30 mm in length and 10 mm in dia. were created by compacting milled powders under pressure of 540 MPa for 2 minutes. Green shaped cylindrical specimens were held at 900, 950, and 1000 degrees Celsius for 2 hours at the maximum temperature. Composite samples were tested for hardness and compressive strength. Specimens' microscopic structures were studied with the help of a variety of analytical tools, including an optical microscope, SEM, and EDS. In composites having copper matrix, reinforcement phase was found to be uniformly dispersed throughout the material. Compression strength in composites was increased by about 108% at 5 wt.% of Gr.-TiC reinforcement and by about 34% at 10 wt.% of reinforcements (Gr.-TiC). When Gr.-TiC reinforcement was added to a copper matrix at a weight percentage of 15 wt.%, the compression strength significantly decreased. The wear property of the produced composites was enhanced by including Gr.-TiC reinforcement into the copper matrix.

Wear and friction behaviour of Cu-Gr-B4C composites and correlating to the topographical characteristics

“…The observed phenomenon can be attributed to the favorable solid lubricant properties of graphite and the rapid formation of boron oxide (B 2 O 3 ) layer by B 4 C, which played a crucial role in reducing the coefficient of friction [43]. The existing literature indicates that a similar result is observed in situations where a soft matrix contains both rigid titanium carbide and graphite particles [21,44].…”

“…Sintering and the ball milling process are crucial to forming consistent characteristics in MMC [20]. The graphite-based reinforced Different sintering temperatures were used to create copper-based composites, and it was found that the qualities of the composites sintered at 1000 °C were improved [21]. The powder metallurgy technique produces a coppergraphite metal matrix composite that exhibits a reduced friction coefficient compared to the pure copper specimen [22].…”