Mechanics of linear cellular alloys

Mechanical and heat transfer behaviors of extruded metal honeycombs (linear cellular alloys or LCAs) are considered. Certain mechanical and thermal/heat transfer characteristics of this class of honeycomb materials are superior to those of open and closed cell stochastic metal foams of comparable relative density. Moreover, they are potentially well-suited to multifunctional applications that demand not only structural but some other performance attribute such as energy absorption, heat transfer or thermal protection. We first consider theoretical estimates for elastic stiffness and initial plastic buckling strength for a range of simple cell shapes under in-plane (IP) compression, including both cell wall bending- and extension-dominated cell shapes. Then, a series of experiments are presented regarding IP and out-of-plane compressive strength, collapse behavior and energy absorption for both quasistatic and dynamic loading conditions for extruded square cell maraging steel and nickel alloy honeycombs with approximately 25% relative density. Thermal properties and laminar flow heat transfer relations. including upper and lower bounds on total steady state heat transfer for a unidirectional forced flow LCA heat exchanger, are presented for the case of square cells. (C) 2003 Elsevier Ltd. All rights reserved.