Processing of FeAl material by pressure assited volume combustion synthesis and development of properties

Key Words: Intermetallic Compounds, Iron Aluminides, FeAl, FeAl-B, Combustion Synthesis Aluminides have been the subject of scientific interest for more than 20 years because of their attractive physical and mechanical properties. Iron aluminides based on Fe3Al and FeAl are good candidates for use in high temperature structure materials due to their low cost, relatively high melting point, comparatively low density and excellent resistance to oxidation and sulfidation. However, their poor ductility and fracture toughness at room temperature hinder their use as structural materials. These mechanical properties can be improved most efficiently by adding different transition metals. Combustion synthesis is an attractive technique for synthesizing a wide variety of advanced materials, including powders and near-net-shape products of ceramics, intermetallics, composites and functionally graded materials. In combustion synthesis, the exothermicity of the redox chemical reaction is used to produce useful materials. In this new approach the synthesis is obtained through an extremely rapid self-sustainng process driven by the large heat release by the synthesis reaction. In this study FeAl intermetallic materials was produced by pressure assited volume combustion synthesis and effect of adding 1, 4, 7 and 10wt%B on material was investigated. Metallographic studies revealed that optimum production conditions result in production of FeAl intermetallic which has a relative density of 99.45% and phase transformation was completed and free of porosity. SEM studies showed that single and homogeneous FeAl phase is dominant in produced intermetallics and by adding boron the formation of multiphase. XRD patterns showed that; 4 wt%B and 7 wt%B which was added to FeAl leaded to Fe2B phase formation and addition of 10 wt%B leaded to Fe2B and AlFe2B2. The hardness value of FeAl intermetallic material was about 607.8 HV0.05. It was observed that the higher the amount of boron the higher hardness values and the materials hardness which containing 10 wt%B was about 1437.7 HV0.05.