Development of Low Cost Lightweight Aluminum Foam for Railway Transportation

Abstract

Metallic foams are commonly produced using hydride and carbonates foaming agents. However, carbonate foaming agents are safer to handle than hydrides and produce aluminum foam with a fine, homogenous cell structure, low cost and easily available. The number of pores per inch (PPI) and relative density of the foam play an important role on their physical and mechanical properties. Hence it is very important to investigate effect of shell foaming agent on PPI and relative density. The present work deals with the effect of additive amount of the shell forming agent on the physical properties of an AlSi7Mg alloy closed cell foam. The foam was produced with different additive amount of shell (1, 3, 5 wt %) as a foaming agent. The PPI and density of the foam produced with different additive amount of shell as foaming agent are determined. Relative density is in the range of 0.21-0.29, PPI are in the range of 11-19 for the produced AlSi7Mg alloy closed cell foam. Therefore, the appropriate addition amount of shell is 3 % by weight for production of a uniform cell structure from the viewpoints of efficiency and economy.