Densification, Microstructural Evolution, Mechanical Properties and Oxidation Study of CrB2 + EuB6 Composite

  • K. Raju
  • J. K. Sonber
  • T. S. R. Ch. Murthy
  • K. Sairam
  • S. Majumdar
  • V. Kain
  • G. V. S. Nageswar Rao


This paper reports the results of investigation on densification, microstructural evolution, mechanical properties and oxidation study of CrB2 + EuB6 composite. CrB2 + EuB6 (10 and 20 wt.%) composites have been fabricated by hot pressing at a temperature of 1700 °C and 35 MPa pressure. The hardness and flexural strength were measured in the range of 21.25-24.48 GPa and 171-199 MPa, respectively. The fracture toughness increased from 3.3 to 4.01 MPa m1/2 by the addition of 20% EuB6. Microstructural evolution revealed the uniform distribution of EuB6 and absence of any reaction product. Fracture surface analysis confirmed the presence of transgranular mode of fracture. Oxidation study at 1200 °C revealed that the developed composites have good oxidation resistance and followed the parabolic rate of oxidation.


CrB2 EuB6 hot pressing mechanical properties microstructure oxidation 


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Copyright information

© ASM International 2018

Authors and Affiliations

  • K. Raju
    • 1
  • J. K. Sonber
    • 2
  • T. S. R. Ch. Murthy
    • 2
    • 3
  • K. Sairam
    • 2
    • 3
  • S. Majumdar
    • 2
    • 3
  • V. Kain
    • 2
    • 3
  • G. V. S. Nageswar Rao
    • 1
  1. 1.Department of Metallurgical and Materials EngineeringNational Institute of TechnologyWarangalIndia
  2. 2.Materials Processing and Corrosion Engineering DivisionBhabha Atomic Research CentreMumbaiIndia
  3. 3.Homi Bhabha National InstituteMumbaiIndia

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