INFLUENCE OF SURFACE MODIFICATION ON COMPRESSIVE PROPERTIES OF CLOSED CELL ALUMINUM FOAM

Abstract

Aluminum foams have been increasingly used in automotive and aerospace applications due to their high strength-to-weight ratio, good impact resistance and excellent energy dissipation capacity. Foamed aluminum does not have sufficient strength for some commercial uses. Several methods have been suggested to improve the strength characteristics of foamed aluminum. Here, also one of the strength improving method was suggested to improve the compressive properties of the closed cell aluminum foam. In this present work aluminum foam with a closed cellular structure was prepared by a liquid melt foaming method. Standard Epoxy Adhesive (Araldite) and Synthetic Resin Adhesive (Fevicol SH) were used for surface modification on closed cell Aluminum foam. Three type specimens (Af, Ar, F) were used to analyze the influence of surface modification on compressive properties. The compression tests were carried out on all specimens at strain rate of 6.25x10-3 sec'. Compressive properties of Al foam were improved after surface modified with Standard Epoxy Adhesive (Araldite). This result was due to suppression of buckling of cell wall by infilling open surface pores. `F' type specimens (Synthetic Resin Adhesive (Fevicol SH)) did not much influence on improving the compressive properties. These results were empathized by analyzing the fracture mechanism and size effect on the three types of specimens.