Evaluation of Intermetallic Reaction Layer Formation Within Steel Encapsulated Metal Matrix Composites

Abstract

Macro hybridized systems consisting of steel encapsulated light metal matrix composites (MMCs) deliver a low cost/light weight composite with enhanced mechanical properties. By exploiting the high strength, modulus, and damage tolerance of steels and the high stiffness and low density of MMCs the resultant macro hybridized systems alleviates the high density of steel and the poor ductility of MMCs. The resultant system, when properly designed, offers higher specific properties and a more structurally efficient system can be attained. However, the combination of these dissimilar materials, specifically iron and aluminum, often results in the formation of intermetallic compounds. In certain loading situations, these typically brittle intermetallic layers can result in degraded performance. In this research, X-ray Diffraction (XRD), X-ray Energy Dispersive Spectroscopy (EDS), and Electron Backscatter Diffraction (EBSD) are utilized to characterize the intermetallic reaction layer formed between an aluminum or magnesium MMCs reinforced with Al2O3, SiC, or B4C particles and encapsulated by A36 steel, 304 stainless steel, or Nitronic® 50 stainless steel.