Strengthening mechanism of TiC/Al composites using Al-Ti-C/CNTs with doping alloying elements (Mg, Zn and Cu)

Abstract

The nano-TiC/Al composites with different alloying elements (Zn, Cu and Mg) were successfully prepared via a one-step method of reaction and densification in the reaction system of Al-Ti-C/CNTs. With the addition of alloying elements, the exposed crystallographic plane of TiC changed from (100) to (111). And the crystallographic mismatch of TiC(111) and TiC(100) with α-Al was significantly reduced by the Cu and Mg addition. Especially, the Mg addition resulted in 8–10% decrease in the crystallographic mismatch compare to that without alloying element. Consequently, the alloying element addition lead to a significantly increase in the compression strength and wear resistance. With the addition of Mg, the σ0.2 and σUCS of the composite are significantly increased by ∼84.3% and ∼54.7%, respectively. The improvement of interface matching degree plays a leading role in the strengthening of composites.

Keywords

• TiC/Al composites
• Alloying elements
• Crystallographic mismatch
• Mechanical properties