Experimental Study and Thermodynamic Modeling of B-Fe-W System

Abstract

The present study investigates experimentally phase equilibria relations in the B-Fe-W ternary system. For the experimental study, B-Fe-W alloys were produced by arc-melting. These alloys were equilibrated using long-term annealing for 2000 h and 4224 h at temperatures of 1050 and 677 °C, respectively. The alloys were characterized by scanning electron microscopy coupled with energy dispersive x-ray spectroscopy, x-ray powder diffraction analysis, and differential scanning calorimetry. Based on the experimental results, the B-Fe-W system was modeled using the CALPHAD method. Herein, boron was modeled interstitially in the solid solutions of iron and tungsten. Also, in this study, the volume phase fractions for selected B-Fe-W alloys were determined using an image analysis technique.