Abstract

Effect of Boron on Milling and Sintering Behavior of Iron Powders

Author(s): Vikrant Saumitra*, Shubham Kumar Ekghara

 The rise of the iron based metallurgy industry has been aided significantly by advances in the knowledge of powder sintering. Sintering can take place both in a solid state and in the presence of a liquid phase. The sintering of iron powder containing B is mentioned in this article. Even though iron-boron compositions are frequently sintered to high densities, they have poor mechanical characteristics. The effect of adding 1% B to iron powders on density, microstructure development and strength was investigated. The specimens were sintered for 45 minutes at 1200°C. The inclusion of B resulted in an increase in specimen density and the creation of a new microstructure type. B interacts with the matrix, according to microstructural studies. Scanning microscopy and energy dispersive spectroscopy analysis were used to investigate the evolution of microstructure and chemical composition. With increased milling time, thermal behaviors evaluated using differential scanning calorimetry revealed a decrease in melting temperature and an increase in exothermic effects. X-ray diffraction was used to investigate the phase transformations that occurred inside the material is during milling and sintering, revealing the development of Fe₂₃(B, C)6 and Fe₂₃B6 intermetallics. In phase diagrams of these alloy systems, B forms steepened liquidus of Fe-B and Fe-B-C. Fast densification and spheroidization of pores occur after the creation of eutectic liquids within the alloys, resulting in improved mechanical characteristics. B is identified only within the particle boundary area of plain iron and Fe-C steels, resulting in a combination of boride and borocarbide. In combination with a border borocarbide network, eutectoid Fe-C steel generates a ferritic surface layer on particles. The increased density indicated that the materials had a stronger microhardness and strength. The trend for grain coarsening was amplified with sintering temperature because particle size decrease was enhanced by B addition.