Abstract

ABASOLO, J. A; GARCIA-BORQUEZ, A  and  KESTERNICH, W. TRANSMISSION ELECTRON MICROSCOPY CHARACTERIZATION OF RADIATION-INDUCED PRECIPITATES WITH HIGH ENERGY IONS IN STABILIZED AUSTENITIC STEELS. Rev. LatinAm. Met. Mat. [online]. 2002, vol.22, n.2, pp.82-87. ISSN 0255-6952.

In the present work techniques such as Bright Field (BF), Stereomicroscopy, Convergent Beam Electron Diffraction (CBED) and X-ray Energy Dispersive Spectrometry (EDS) were used in order to characterize microstructurally radiation-induced precipitates (RIP) with Ni++ ions irradiation in 1.4970 (Ti stabilized) and 1.4981 (Nb stabilized) austenitic stainless steels at 600 and 650 ºC, respectively. The 3.66 MeV Ni++ ions were originally generated in a Tandetron linear accelerator so that the irradiation doses of 360 and 1800 dpa were produced in each steel. Transmission Electron Microscopy (TEM) samples were electrochemically thinned by using the Controlled Depth Preparation technique. For both irradiation doses, a higher number density of RIP was found in the 1.4981 than in the 1.4970. It was also found that most of the RIP correspond with the G cubic phase, fact that was confirmed when computer simulations of dynamical CBED patterns were performed. Most of the RIP shapes are plate-like and its growing crystallographic direction develops mainly along the [011]. Crystallographic and morphological alignment was also found between RIP and matrix (g phase).

Keywords : Radiation-Induced Precipitation (RIP); Convergent Beam Electron Diffraction (CBED); Controlled Depth Preparation; displacement per atom (dpa); Stereomicroscopy.