Investigation Of Hardness Anisotropy In Tourmaline

M.O. Adeoye, O.O. Adewoye

Department of Metallurgical and Materials Engineering,Obafemi Awolowo University,Ile-Ife.Nigeria.
Engineering Materials Development Institute, Akure, Nigeria.

DOI: 10.4236/jmmce.2004.32011                

Abstract

Tourmaline is a ring silicate material with a hexagonal crystal structure. Tourmaline crystal is made use of as an electronic component, e.g, as a transducer, mainly because of the anisotropy it exhibits in its properties. Microindentation technique was employed in the research reported in this paper, using a Knoop indenter, to investigate the anisotropy in the hardness of the tourmaline crystal on its two major crystallographic planes: (0001) and {10 10}. The material was found to exhibit hardness anisotropy in conformity with its rotary symmetry elements. The material was identified and analysed using various x-ray techniques, and was found to contain some impurities as expected of natural crystals. Tourmaline was found to have a Si/Al ratio of 1.4. The orientations of the crystal samples were determined by obtaining and indexing the Laue x-ray back-reflection patterns of the crystal samples.

Keywords

Tourmaline, Hardness anisotropy, Microhardness, Knoop

Conflicts of Interest

The authors declare no conflicts of interest.

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