Metallurgical and Materials Transactions A

, Volume 42, Issue 6, pp 1431–1434 | Cite as

Effect of Strain Rate on Ductile-to-Brittle Transition Temperature of a Free-Standing Pt-Aluminide Bond Coat

  • Md. Zafir Alam
  • D. Chatterjee
  • K. Muraleedharan
  • T. K. Nandy
  • S. V. Kamat
  • V. Jayaram
  • D. K. Das
Communication
  • 153 Downloads

Abstract

The ductile-to-brittle transition temperature (DBTT) of a free-standing Pt-aluminide (PtAl) bondcoat was determined using the microtensile testing method and the effect of strain rate variation, in the range 10−5 to 10−1 s−1, on the DBTT studied. The DBTT increased appreciably with the increase in strain rate. The activation energy determined for brittle-to-ductile transition, suggested that such transition is most likely associated with vacancy diffusion. Climb of 〈100〉 dislocations observed in analysis of dislocation structure using a transmission electron microscope (TEM) supported the preceding mechanism.

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Copyright information

© The Minerals, Metals & Materials Society and ASM International 2011

Authors and Affiliations

  • Md. Zafir Alam
    • 1
  • D. Chatterjee
    • 1
  • K. Muraleedharan
    • 1
  • T. K. Nandy
    • 1
  • S. V. Kamat
    • 1
  • V. Jayaram
    • 2
  • D. K. Das
    • 1
  1. 1.Defence Metallurgical Research LaboratoryHyderabadIndia
  2. 2.Indian Institute of ScienceBangaloreIndia

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