Micro-alloying assisted consolidation of aluminum/carbon nanotubes powder

A highly-dense aluminum (Al)/carbon nanotubes (CNTs) composite is produced via a two-step consolidation process for micro-alloying assisted sintering after hot pressing. First, Al–5 vol% CNTs powder is covered with zinc (Zn) flakes by mechanical milling. During high-pressure pressing at 500 °C, the Zn flakes melt along the Al/CNTs powder boundaries by capillary action, providing the initial densification. Further densification is accomplished by micro-alloying Zn and Al atoms during sintering at 450 °C. The composite with 4 vol% Zn shows ~98% relative density and ~520 MPa compressive strength after precipitation hardening.