Journal of Failure Analysis and Prevention

, Volume 19, Issue 6, pp 1537–1543 | Cite as

Preventative Metallurgical Failure Evaluation of Free Power Turbine Nozzle of Aero-Derivative Gas Turbine Engine

  • Sulaiman A. Al-Baltan
  • Alaaeldin H. MustafaEmail author
  • Shouwen Shen
Lessons Learned


A set of free power turbine first stage nozzle guide vanes (NGVs) was investigated with the objective of extending its service life after completing 100,000 operating hours. The investigation covered material microstructure examination, mechanical properties, physical parts visual inspection as well as predicting the formation of deleterious phases. New and removed from service NGVs were used as investigation vehicles with testing specimens taken from the NGV root, 10, 50 and 90% span wise direction. Optical microscopy, scanning electron microscopy and XRD were used in the analysis. The investigation concluded that there were no secondary phases formation due to the operation in the as-removed NGV and Nv for both new and as removed from service NGVs were below the specific superalloy Nv limit.


Free power turbine NGV Nv 



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Copyright information

© ASM International 2019

Authors and Affiliations

  • Sulaiman A. Al-Baltan
    • 1
  • Alaaeldin H. Mustafa
    • 1
    Email author
  • Shouwen Shen
    • 2
  1. 1.Mechanical Services Shops DepartmentSaudi AramcoDhahranSaudi Arabia
  2. 2.Research and Development CenterSaudi AramcoDhahranSaudi Arabia

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