Design of Intermetallic Mg (Recycled Ti-Al) Based Composites Through Semi Powder Metallurgy Method

摘要

Structural materials should be stronger, tougher, and lighter to withstand the extreme conditions in the aeronautic and automotive applications. In this work, alternative intermetallic based composites (IMBCs) were designed from Mgx (1-x) Ti-Al recycled intermetallic alloy reinforced with the different percentages of CNT/Al_2O_3 fiber and Boron/Al_2O_3 fiber. Aluminum powder (～5 wt %) obtained from fresh scrap was added to the compositions to improve the homogenization of the mixture. Then, final composites were produced through sintering, combined method of sintering followed by forging and/or sintering followed by thixoforming which are low cost and efficient methods to manufacture light, multifunctional materials. Two different composites were designed by using these manufacturing processes: First group was considered as matrix +0.5 wt % CNT +1% Al_2O_3 fiber and the second group was designed as matrix +0.5wt % Boron +1% Al_2O_3 fiber. Quasi-static compression tests, nanoindentation (wear, modulus, hardness) test were performed to study the effect of the reinforcements and the manufacturing methods. The microstructure analyses (matrix/interface) have been carried out by Scanning Electron Microscope (SEM).