Microstructure and Mechanical Properties of NiTi₂-TiB Composite Fabricated by Spark Plasma Sintering

Masashi Yoshida^*, Hideo Shiraishi, Naoya Ikki

Department of Mechanical Engineering, Ube National College of Technology, Ube, Yamaguchi 755-8555, Japan.

DOI: 10.4236/wjet.2015.33C013                

Abstract

Composites of NiTi₂-TiB have been fabricated using spark plasma sintering and mechanical properties have been investigated. Dense specimens of monolithic NiTi2 have been obtained by the sintering at 950?C. By the x-ray diffraction measurements it has been shown that NiTi₂ co-exists with TiB in equilibrium at 950?C. The bending strength of NiTi₂-TiB composite increases with increasing the volume fraction of TiB2 up to 60 vol%. The maximum bending strength of 730 MPa has been obtained for NiTi₂-60vol% TiB₂. The Vickers hardness also increases with increasing the volume fraction of TiB up to 70% and the highest Vickers hardness of 1620 Hv has been obtained for NiTi₂-70%TiB.

Keywords

Composite, Bending Strength, Vickers Hardness, TiB, NiTi₂

Conflicts of Interest

The authors declare no conflicts of interest.

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