Influence of metallic dopants on fracture behaviour of TiB2 based cermets

0421219 - ÚFM 2014 RIV SK eng J - Journal Article
Chlup, Zdeněk - Bača, L. - Halasová, Martina - Šajgalík, P.
Influence of metallic dopants on fracture behaviour of TiB2 based cermets.
Acta Metallurgica Slovaca Conference. - (Šebeková, H.). Roč. 3, č. 1 (2013), s. 98-105. ISSN 1338-1660.
[FRACTOGRAPHY 2012. Stará Lesná, 21.10.2012-24.10.2012]
R&D Projects: GA ČR(CZ) GAP108/11/1644; GA MŠMT(CZ) ED1.1.00/02.0068
Institutional support: RVO:68081723
Keywords : hot pressing * mechanical alloying * mechanical milling * bending test * toughness * cermets
Subject RIV: JL - Materials Fatigue, Friction Mechanics

Titanium diboride (TiB2) - metal composites were prepared by hot-pressing of the TiB2 - Ni and Ta doped TiB2-Ni powders. The obvious limitation of pure TiB2 is the bad sinterability, exaggerated grain growth at temperatures exceeded 2000°C needed for the densification and brittleness. There is only limited number of approaches how to improve fracture resistance. The method used in this work is based on doping the basic microstructure by above mentioned metals. The positive influence of dopants on the microstructure and fracture behaviour was demonstrated by means of mechanical properties and fractographic analysis. The right selection of dopants led to the refinement of microstructure resulted in the increase of flexural strength up to the level of 700 MPa and fracture toughness of 5.0 MPa.m1/2.
Permanent Link: http://hdl.handle.net/11104/0228238