INVESTIGATION OF THE MECHANICAL PROPERTIES OF AlSi9Cu3(Fe)/MWCNT NANOCOMPOSITES PREPARED BY HPDC

摘要

In this research, an often-used high-pressure die-casting (HPDC) AlSi9Cu3(Fe) alloy was chosen as the matrix for an Al-alloy/MWCNT nanocomposite material that could be, in the case of targeted mechanical properties, used for the production of lighter car parts. In the industrial experiment, nanocomposite samples were prepared by a HPDC machine from a base AlSi9Cu3(Fe) alloy with three different mass ratios of MWCNTs placed on two different positions inside the casting machine. The structure and thermal stability of the used MWCNTs were visually confirmed by scanning electron microscopy (SEM). The microstructural and metallographic properties were studied using an optical microscope. The mechanical properties (tensile strength, elongation at break and hardness) were investigated using a universal testing machine and a Vickers hardness tester. The experimental results of this research showed that the HPDC-prepared Al-alloy matrix nanocomposite material had significantly changed mechanical properties even with small MWCNT contents. The elongation at break and the tensile strength of the Al-alloy/MWCNT nanocomposite were increased in comparison with the base alloy. The finest microstructure was shown by samples with 0.05 w/% MWCNTs, which was in correlation with the most significant change in the mechanical properties.