TOLLEY Alfredo Juan
Nucleation, growth and coarsening of gamma-precipitates in a Ni-Cr-Al-based commercial superalloy during artificial aging.
A. PICASSO; A. SOMOZA; A. TOLLEY
JOURNAL OF ALLOYS AND COMPOUNDS
ELSEVIER SCIENCE SA
Año: 2009 vol. 479 p. 129 - 129
A study of the decomposition kinetics of the IN-X750 Ni-based superalloy using positron annihilation lifetime spectroscopy (PALS), microhardness and transmission electron microscopy (TEM) is presented. PALS results confirmed that nucleation and growth of gamma prime precipitates are assisted by vacancies. Due to the high sensitivity of positrons for vacancy-like defects, information regarding vacancy-solute clustersformed during the very early stages of aging was obtained. The positron lifetime and TEM results were analyzed following classical precipitation models to interpret the kinetics of the gamma prime precipitate formation. Finally, from TEM measurements a value of the gamma prime precipitate coarsening rate for the alloy studied was obtained.