Heat-Treated Ni-CNT Nanocomposites Produced by Powder Metallurgy Route

Area of Science:

• Materials Science
• Nanotechnology
• Metallurgy

Background:

• Nickel-carbon nanotube (CNT) nanocomposites are promising for automotive and aerospace applications.
• Thermal stability is a critical factor for materials used in high-temperature environments.
• Understanding microstructural evolution under heat is essential for predicting mechanical properties.

Purpose of the Study:

• To investigate the microstructural evolution of nickel-carbon nanotube (Ni-CNT) nanocomposites after heat treatment.
• To evaluate the effect of varying CNT content on thermal stability.
• To compare the behavior of Ni-CNT nanocomposites with unreinforced nickel.

Main Methods:

• Powder metallurgy was used to produce Ni-CNT nanocomposites with varying CNT concentrations.
• Ultrasonication ensured uniform CNT dispersion.
• Heat treatments were conducted under high vacuum at 700 and 1100 °C.
• Microhardness testing assessed mechanical properties.
• Scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and high-resolution TEM were employed for microstructural analysis.

Main Results:

• The study successfully analyzed the microstructural changes in Ni-CNT nanocomposites subjected to heat treatment.
• Microhardness tests indicated how mechanical properties were affected by thermal exposure.
• Advanced microscopy techniques provided detailed insights into the material's behavior at high temperatures.

Conclusions:

• The presence of carbon nanotubes (CNTs) positively influences the thermal stability of nickel nanocomposites.
• The findings suggest that Ni-CNT nanocomposites are suitable for high-temperature applications.
• Further research into optimizing CNT content and processing parameters is warranted.