Analysis of ISE in microhardness measurements of bulk MgB2 superconductors using different models


Kolemen U.

JOURNAL OF ALLOYS AND COMPOUNDS, vol.425, no.1-2, pp.429-435, 2006 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 425 Issue: 1-2
  • Publication Date: 2006
  • Doi Number: 10.1016/j.jallcom.2006.01.075
  • Title of Journal : JOURNAL OF ALLOYS AND COMPOUNDS
  • Page Numbers: pp.429-435
  • Keywords: superconductors, mechanical properties, indentation size effect (ISE), VICKERS HARDNESS, POLYCRYSTALLINE SUPERCONDUCTORS, INDENTATION, NANOINDENTATION, LOAD, CERAMICS, MODULUS

Abstract

The indentation load-displacement curves of the MgB2 sample are drawn by different peak load levels ranging from 300 to 1500 mN. Microhardness values are calculated from loading-unloading curves. The results show that the hardness values exhibited peak load dependence, i.e., indentation size effect (ISE) on intermetallic MgB2 superconductors. The peak load dependence is analyzed by using the Meyer's law, the Hays-Kendall approach, the Elastic/Plastic Deformation model, the Proportional Specimen Resistance model (PSR), and the Modified PSR models. As a result, Modified PSR model is found to be the most effective one for microhardness determination of intermetallic MgB2 superconductor. (c) 2006 Elsevier B.V. All rights reserved.