Microstructural Characterization of Al/CNTs Nanocomposites after Cold Rolling

Area of Science:

• Materials Science
• Mechanical Engineering
• Nanotechnology

Background:

• Metal matrix nanocomposites, particularly Al/CNTs, offer potential for advanced components in the mobility industry.
• Powder metallurgy is a key production process for these nanocomposites, necessitating research into their deformation behavior.
• Understanding deformation is crucial for optimizing microstructure and mechanical properties by reducing porosity.

Purpose of the Study:

• To investigate the deformation behavior of Al/CNTs nanocomposites during cold rolling.
• To evaluate the reliability of the powder metallurgy route followed by cold rolling for Al/CNTs nanocomposites.
• To analyze the influence of CNTs on microstructure, crystallographic orientation, and mechanical properties.

Main Methods:

• Production of Al/CNTs nanocomposites via powder metallurgy.
• Microstructural characterization using optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD).
• Mechanical characterization including hardness and tensile strength testing during cold rolling.

Main Results:

• The powder metallurgy route combined with cold rolling is effective for Al/CNTs nanocomposites.
• Microstructural analysis revealed distinct crystallographic orientations in nanocomposites compared to the Al matrix.
• CNTs influence grain rotation during sintering and deformation, leading to different texture evolution and an initial decrease in hardness and strength due to the Bauschinger effect.

Conclusions:

• Cold rolling of powder metallurgy-produced Al/CNTs nanocomposites is a viable method for property enhancement.
• The presence of CNTs significantly alters the crystallographic texture and deformation mechanisms.
• Differences in texture evolution between Al/CNTs nanocomposites and the Al matrix account for variations in mechanical properties during cold rolling.