Interpretation of Self‐Diffusion and Vacancy Properties in Gold

Abstract

Measurements of the self-diffusion coefficient and the high-temperature equilibrium concentration of vacant lattice sites in gold are reanalysed in a critical manner. The analysis takes into account divacancy contributions and temperature dependences of the activation energies and entropies. A consistent set of self-diffusion and vacancy parameters is derived. Previous interpretations, in particular those of Stoebe and Dawson [25]. and Wang, Seidman, and Balluffi [20], are criticized. Selbstdiffusionsdaten und Messungen der Gleichgewichtskonzentration leerer Gitterplitze von Gold werden in kritischer Weise analysiert. Die Analyse beriicksichtigt einen Beitrag von Doppelleerstellen eowie eine Temperaturabhiingigkeit der Aktivierungsenergien und -ent+opien. Ein in sich konsistenter Satz von Selbstdiffusions-und Leerstellenparametern wird abgeleitet. Vorhergehende Interpretationen, insbesondere diejenigen von Stoebe und Dawson [25] sowie Wang, Seidman und Balluffi [20], werden kritisiert. 33, 2776 (1962). lished).

Analysis of tracer and nuclear magnetic resonance measurements of self‐diffusion in aluminium

“…All these quantities refer to the reference temperature To for which we take To = 273 "K. u is the temperature coefficient of the activation parameters. The five adjustable parameters were fitted to the tracer data [5,6] and the NMR-data of Sun [26] by the least-square procedure described earlier [53]. The result of the fit is shown in Fig.…”

Quenching Studies of Lattice Vacancies in High-Purity Aluminium

“…a temperature dependence of the enthalpies and entropies of formation and migration, or contributions from defects other than monovacancies. The matter was discussed in detail elsewhere 45,46) with the conclusion 45) that in most fcc metals (including Al 47) ) showing strongly curved Arrhenius (or Boltzmann) plots, the curvatures are mainly due to divacancies present in hightemperature thermal equilibrium. (An analogous statement would presumably not be true for bcc metals.…”

“…Furthermore, such an assumption would destroy the agreement between the H B 2V to be derived from high-temperature data with the 'low-temperature' value deduced from annealing experiments by Doyama and Koehler 48) and by Levy, Lanore, and Hillairet 49,50) to be referred to presently. Our analysis followed the Seeger-Mehrer 45,46) procedure. By averaging the data of Simmons and Balluffi, 39) Bianchi et al, 40) von Guérard et al, 41) and Mosig, (17) to be a good estimate for the monovacancy formation entropy in Al.…”

QUANTITATIVE STUDY OF VACANCY DEFECTS IN QUENCHED PLATINUM BY FIELD ION MICROSCOPY AND ELECTRICAL RESISTIVITY. II. ANALYSIS AND INTERPRETATION. Report No. 1786.

“…6) employing'the residual surface activity technique They cal- (16) culated a value of DT = (0.22t0.03)exp(-2.89ev/kT)cm2sec Peterson (18) (19) in his review article on "Diffusion in Metals" favors the Kidson and Ross In view of these facts, we regard as unsatisfactory the fitting of these data to a common curve with equal weight given to each data point.…”

“…The velocity v was measured experimentally and was found to be =2x10 cm -1 sec Using the previous expressions for the defect diffusivities, equations (19) and (20) predict denuded zones of negligible width; i.e.. X and X 1v 2v…”