The structural properties of Fe-Ti-B based alloys produced by mechanical alloying

Abstract

In the present study, the production of Fe-Ti-B based alloys was realized and their structure and properties were investigated. Mechanical alloying proceeds by the continual cold welding and fracturing of the constituent mixture of Ti+4B+5Fe powder when subjected to the large compressive forces of a high speed mill. The powder charge together with 7 mm diameter steel balls were loaded into a tool steel grinding container at approximately 350 RPM for 20 h. The samples were shaped as cylinder of Ø15×8 mm dimensions by uniaxial pressing at 450 MPa. Then, the green body materials were produced by sintering at 1100 °C for 1-4 h in argon atmosphere. The morphology of composite materials was investigated by optical microscopy and scanning electron microscopy and phase analysis was realized by x-ray diffraction analysis. The bulk densities of the materials were measured using by Archimedes method. Also, the micro-hardness of the samples was measured by Vickers indentation technique. As a result, Fe, iron boride (FeB, Fe2B) and titanium boride (TiB2) phases were detected in the phase analysis of the Fe-Ti-B based materials. The hardness of the materials was measured between 1107 HV0:05 and 1551 HV0:05, depending on sintering time. The densities of the samples were determined between 4.205 g/cm3 and 4.219 g/cm3.