Investigation of mechanisms of blade failure of forged Hastelloy B and cast Stellite 21 turbine blades in turbojet engine Page: 4 of 43
This report is part of the collection entitled: National Advisory Committee for Aeronautics Collection and was provided to Digital Library by the UNT Libraries Government Documents Department.
The following text was automatically extracted from the image on this page using optical character recognition software:
NACA RM E51D16 3
As part of the over-all program to investigate heat-resistant alloys
for use in turbojet engines, an investigation was conducted at the
NACA Lewis laboratory to determine the high-temperature properties
that define the turbine-blade life of a forged nickel-base alloy,
Hastelloy B, and a precision case cobalt-base alloy, Stellite 21.
The blades were alternately mounted in a 16-25-6 alloy rotor and
operated under cyclic (simulated service) conditions in a J33-9
turbojet engine. At intervals during the engine operation, the
turbine blades were measured to determine the amount of blade creep
and inspected for evidence of failure or damage. Simultaneously with
the engine operation high-temperature stress-to-rupture tests were
conducted of specimens cut from the airfoil section of blades of each
alloy to allow a comparison of the stress-rupture life of the blade
with engine life. At the conclusion of operation, all blade and
stress-rupture specimen failures were examined metallurgically to
determine the nature of the origin of failure and the mechanism of
APPARATUS AND PROCEDURE
Fabrication history. -
Nominal Stellite 21 Hastelloy B
chemical (reference 1) (manufacturer's data)
C Cr Mo Ni C Mo Fe Ni
0.20- 25.00- 5.00- 1.75- 0.12 26.0- 4.0- Remain-
.35 29.00 6.00 3.75 max. 30.0 7.0 der
Mn Si Fe Co
1.00 1.00 2.00 Remain-
max. max. max. der
Fabrication Precision cast Forged
Heat treatment None 2 hr at 19000 F, air-
4 hr at 15000 F, air-
Here’s what’s next.
This report can be searched. Note: Results may vary based on the legibility of text within the document.
Tools / Downloads
Get a copy of this page or view the extracted text.
Citing and Sharing
Basic information for referencing this web page. We also provide extended guidance on usage rights, references, copying or embedding.
Reference the current page of this Report.
Yaker, C.; Robards, C. F. & Garrett, F. B. Investigation of mechanisms of blade failure of forged Hastelloy B and cast Stellite 21 turbine blades in turbojet engine, report, August 22, 1951; (https://digital.library.unt.edu/ark:/67531/metadc58828/m1/4/: accessed April 24, 2019), University of North Texas Libraries, Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.