Matériaux & Techniques
Volume 83, 1995Matériaux intelligents. Corrosion sous contrainte. Essai de dureté
|Page(s)||56 - 58|
|Published online||21 June 2017|
II - Endommagement à haute température d’un superalliage monocristallin AM1
Environment effects at high temperature on fatigue damage of the <001> single crystal superalloy AM1
In order to improve the efficiency of gas turbine for jet engines, motorists employ materials which must respond to severe demands at high temperature. Among them, the superalloys obtained by using directional solidification present the best high temperature capability. Such superalloys still have small micro- structural defects The Ni-base AMI used for the manufacturing of blades is one of them. It is covered with a Cr-NiAl coating so as to ensure protection against oxydo-corrosion .
The aim of this study is to assess the experimental importance of creep, fatigue and oxydation on damage mechanisms at 950°C on coated AMI. Notably, we study the initiation and the propagation processes in relation with microstructural defects or the deposit, and the influence of environment on these. For that, fatigue tests are made on coated and uncoated specimens at 950°C in vacuum as well as in the air of the laboratory.
For all specimens, fatigue tests performed in vacuum revealed far less damage than those performed in air. In spite of this, for the stress levels applied until now, we did not observed any influence on fatigue lives but only on crack initiation. In particular, the deposit seems to play a different role on crack initiation according to the environment conditions of testing.
© SIRPE 1995
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.