Experimental investigations and thermodynamic modeling in the ZrB2-Ni section of the B-Ni-Zr system

An investigation of melting equilibria in the Ni-rich part of the B-Ni-Zr system was carried out by means of a combined experimental and computational approach, in order to improve the interpretation of wetting experiments of B-Ni alloys on ZrB2 substrates. Several samples along the Ni-ZrB2 vertical section, close to the Zr-2(Ni21-xZrx)B-6 ternary phase, were prepared by arc-melting the pure metals; the samples were thoroughly studied by means of powder X-ray diffraction and SEM-EDS, and then analyzed by DTA in order to obtain their transition temperatures. The results were used to improve the CALPHAD thermodynamic modeling of the B-Ni-Zr system. A solubility range of the ternary phase between x = 0.14 and x = 0.68 was detected, due to the mixing of Zr and Ni in the 4a crystallographic site. (C) 2014 Published by Elsevier B.V.