Samples of fully lamellar Ti44Al8Nb1B have been tested in tension at room temperature whilst they were interfaced to an acoustic emission system. The generation of signals at stresses well below the 0.2% proof stress has been shown to be due to the formation of cracks within individual colonies. Cracks, introduced by stressing at 0.95 of the 0.2% proof stress act as failure sites and lead to failure at stress levels of 0.65 of the 0.2% proof stress on subsequent testing in tension-tension fatigue at room temperature. The lower fatigue limits of the stronger TiAl alloys as compared with the weaker TiAl alloys are argued to be associated with cracking at low stresses.
|Number of pages||6|
|Journal||International Journal of Materials and Product Technology|
|Issue number||SPEC. ISS. VOL.1|
|Publication status||Published - 1 Dec 2001|
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