Bulk Diffusion of Homovalent Atomic Probes of Scandium, Lanthanum and Thorium in Single Crystals of Tungsten

Abstract:

Article Preview

The volume diffusion of nonmagnetic homovalent atomic probes (APs) from the IIIB group of the periodic table of the elements (PTE)Sc, La, and Th in Whas been studied by the method of secondary ion mass spectrometry. The Arrhenius dependences have the following parameters: the coefficients DSc - (D0)Sc = (1.4  0.3)10-4 m2s-1 and QSc = (546±4) kJ/mole; the coefficients D¬La - (D0)La = (1.6  0.8)×10-6 m2s-1 and QLa = (41010) kJ/mole; and the coefficients DTh - (D0)Th = 4.4×10-6 m2s-1 and QTh = 447 kJ/mole. It has been found that the coefficients D5dAP(Tm)W of the bulk diffusion of transition 5d APs in W coincide at its melting point (Tm)W. The enthalpies, QWSc,La,Th, of the volume diffusion of nonmagnetic homovalent APs from the IIIB group of PTE increase linearly with decreasing relaxation volumes, , of these APs, which interact with vacancies in W. The sums, (Q + E)WSc,La,Th, of the bulk diffusion enthalpies, QWSc,La,Th, and the relaxation energy, (E)WSc,La,Th, of the environments of homovalent APs diffusing to W are nearly constant.

Info:

Periodical:

Defect and Diffusion Forum (Volumes 305-306)

Edited by:

David J. Fisher

Pages:

1-13

DOI:

10.4028/www.scientific.net/DDF.305-306.1

Citation:

S.M. Klotsman et al., "Bulk Diffusion of Homovalent Atomic Probes of Scandium, Lanthanum and Thorium in Single Crystals of Tungsten", Defect and Diffusion Forum, Vols. 305-306, pp. 1-13, 2010

Online since:

October 2010

Export:

Price:

$35.00

In order to see related information, you need to Login.

In order to see related information, you need to Login.