Effects of Cr on the properties of Mo2NiB2 ternary boride

New sintering technique named Reaction Boronizing Sintering has successfully developed world first ternary boride base cermets with excellent mechanical properties such as Mo2FeB2 and Mo2NiB2 base ones. For the prediction of the cermet properties it is very important to know the physical properties of the component materials. In this study 0, 5, 10 and 15 mass% Cr containing Mo2NiB2 ternary borides were prepared to investigate the properties of the hard phase in the cermets. Crystal structure of Mo2NiB2 ternary boride changed from orthorhombic to tetragonal around at 15 mass% Cr. Cr added Mo2NiB2 ternary borides, especially 10 and 15 mass% Cr added borides exhibit high hardness and high elastic modulus comparable to WC and TiC. Cr containing Mo2NiB2 ternary boride is suitable alternative materials to wear resistant hard materials such as WC.

Graphical abstractMicro Vickers hardness of Cr containing Mo2NiB2 ternary borides sintered at 1623–1723 K as a function of Cr content.Figure optionsDownload full-size imageDownload as PowerPoint slide