Metal Foams: A Design Guide

Case studies 225
density and high thermal conductivity of the cell edges are essential. The
DUOCEL range of metal foams, which include both aluminum and copper,
offer this combination of properties. The figure shows a foamed aluminum
heat exchanger for a space-shuttle atmospheric control system.
17.6 Light weight conformal pressure tanks
Fluids in pressure tanks, ranging from aircraft fuel to liquid nitrogen cryogen
for airborne infrared telescopes, must be maintained at constant and uniform
temperature, uniform pressure, and – in moving systems – must be restrained
from ‘sloshing’ because this generates pressure gradients. Figure 17.9 shows
the design of a tank which exploits ERG DUOCEL ® open-celled aluminum
foam to achieve this. The foam has a low density, occupying only 10% of the
volume of the tank, but it limits fluid motion. The high thermal conductivity
of the cell edges maintains the fluid at a constant temperature, important for
jet fuel. Ł
Figure 17.9 DUOCEL ® foamed aluminum used as the structural core, heat
exchanger and anti-slosh baffle in a lightweight conformal tank. (Courtesy
of ERG)
17.7 Electrodes for batteries
Nickel rechargeable batteries systems, nickel cadmium (NiCd) and nickel
metal hydride (NiMH) are the most widely used batteries for consumer
Ł Contact details: ERG Materials and Aerospace Corporation, 900 Stanford Ave, Oakland, CA
94608, USA. Phone: (510) 658-9785; Fax:(510) 658-7428.