February AMP_Digital

A D V A N C E D M A T E R I A L S & P R O C E S S E S | F E B R U A R Y / M A R C H 2 0 1 9 2 0 using a graphite mold. Composite pow- der was sintered at 550°C and 35 MPa pressure for 10 minutes resulting in a density of >99% theoretical. Figures 10(b) and (c) show a bar and Z-shaped bar, respectively, hot extruded from feedstock composite discs. BENEFITS AND APPLICATIONS A comparison of specific strengths (Fig. 11) demonstrates significant weight savings by using Al-SiC composite over steel, titanium, and Al and Mg alloys. The aerospace and transportation in- dustries could benefit most by using Al-SiC composites. For example, it is estimated that about 40-50% of Al al- loys are used as structural components in commercial aircraft. Typical weight Fig. 7 — Comparison of elastic modulus of Al, Al alloy, and Al-SiC composites. Fig. 8 — Comparison of yield strength of Al, Al alloy, and Al-SiC composites. Fig. 9 — Comparison of ultimate tensile strength of Al, Al alloy, and Al-SiC composites. Fig. 10 — Al-SiC composite parts manu- factured using FAST: (a) net-shape truncated cone; (b) hot-extruded bar; and (c) hot- extruded Z-shaped bar. (c) (b) (a)