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Journal of Materials Science

, Volume 30, Issue 24, pp 6288–6298 | Cite as

On the thin-section size dependent creep strength of a single crystal nickel-base superalloy

  • A. Baldan
Article

Abstract

The combined effects of thin-section size, D, and microcracks on the creep behaviour of the single crystal MAR-M002 were investigated at the creep conditions of 300 MPa and 900 °C. It was observed that the creep rupture life, tR is controlled by the mean microcrack size to thin-section size, (dc/D), (or the total number, (Nm), of the mean-sized microcrack particles across the diameter, assuming D/dc=Nm); reducing Nm continuously improves tR. The creep rupture strain (or ductility), εR, can be improved sharply by increasing the total number, NT, of microcrack particles across the cross-section, NTD2NA, where NA is the number of microcrack particles (cavity density) per cross-section. The behaviour of the creep rupture ductility was interpreted in terms of the weakest link, or “largest-flaw” concept; the observation of the higher proportion of the less likely dangerous (smaller in size) microcracks with increasing NT was the underlining reason for the improvement in ductility.

Keywords

Polymer Ductility Combine Effect Material Processing Creep Behaviour 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Chapman & Hall 1995

Authors and Affiliations

  • A. Baldan
    • 1
  1. 1.Department of Mechanical EngineeringEastern Mediterranean UniversityMersin 10Turkey

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