The Effect of Nanometric α-Al2O3 Addition on Structure and Mechanical Properties of Feal Alloys Fabricated by Lens Technique

Abstract

Results of the first principle study on a fabrication of FeAl intermetallic based alloy with an addition of nanometric αAl2O3 (n-Al2O3) particles by the LENS method and a subsequent characterization of the as received materials’ structure and properties, are shown in the present work. A series of samples were manufactured using LENS technique while a control of temperature and the size of melted metal pool. The presence of ceramics nanoparticles was not directly confirmed by microscopy observations. Neither aluminum nor oxygen content was not elevated in the material with n-Al2O3 content. Although, indirect methods revealed influence of n-Al2O3 addition on the manufactured elements structure. Analyses of porosity has shown that addition of 2% vol. n-Al2O3 significantly decreases this feature (~1%), as compared to the reference material made of pure FeAl intermetallic alloy (~5%). The addition of n-Al2O3 causes an increase of grain size in Fe40Al intermetallic alloy. An oxidation resistance has been also improved what was associated to the n-Al2O3 addition. Four times lower increase of samples mass was noticed for sample with the n-Al2O3 addition as compared to the pure Fe40Al intermetallic alloy.

Keywords

• FeAl intermetallic
• nano-Al2O3 addition
• Laser Engineered Net Shaping (LENS)