Stage III Recovery in Cold-Worked Niobium

Stage III recovery in niobium, cold-worked at room temperature, is investigated by means of electrical resistivity measurements. The associated activation energy is found to be constant in the temperature range 80 to 180 °C and equal to 1.20 ± 0.04 eV. Furthermore, the results indicate that the recovery process can be described as a diffusion-controlled bimolecular reaction which follows Waite kinetics. It is concluded that this recovery is caused by recombination of intrinsic point defects. On the basis of the presently available data the possibility of this recovery being caused by migration of vacancies to trapped interstitials cannot be excluded. In view, however, of the relatively small activation energy found for this stage, and of the direct analogy with stage III recovery in the f.c.c. metals, it is tentatively proposed that stage III recovery in b.c.c. metals is due to interstitial migration to vacancies. Die Erholungsstufe III in kaltverformtem Niob wurde durch Messung des elektrischen Widerstandes untersucht. Es zeigte sich, das die zugehorige Aktivierungsenergie im Temperaturbereich von 80 bis 180 °C konstant und gleich 1,20 ± 0,04 eV ist. Weiterhin ergab sich, das der Erholungsprozes als eine diffusionsbestimmte bimolekulare Reaktion beschrieben werden kann, die nach der sich aus der Waiteschen Theorie ergebenden Kinetik ablauft. Es wird angenommen, das diese Reaktion eine Rekombination von Zwischengitteratomen und Leerstellen ist. Auf Grund der gegenwartig verfugbaren Daten kann nicht ausgeschlossen werden, das diese Erholung durch die Wanderung von Leerstellen zu gebundenen Zwischengitteratomen verursacht wird. Wegen der verhaltnismasig kleinen Aktivierungsenergie und der grosen Ahnlichkeit zur Erholungsstufe III in k.f.z. Metallen erscheint es jedoch wahrscheinlicher, das die Erholungsstufe III in k.r.z. Metallen durch die Wanderung von Zwischengitteratomen zu Leerstellen zustande kommt.

[1]  J. Meakin,et al.  VACANCIES IN QUENCHED MOLYBDENUM SINGLE CRYSTALS , 1964 .

[2]  R. A. Johnson,et al.  Interstitials and Vacancies in α Iron , 1964 .

[3]  A. Roberts,et al.  The nature and annealing behaviour of fission fragment damage in molybdenum , 1964 .

[4]  W. R. Upthegrove,et al.  Theory of liquid diffusion phenomena , 1964 .

[5]  H. Schultz.  Die erholung des Elektrischen Widerstandes von Kaltverformtem wolfram , 1964 .

[6]  A. Seeger.  INTERSTITIAL ATOMS IN NOBLE METALS , 1964 .

[7]  J. Nihoul.  Note on the paper of D. E. Peacock and A. A. Johnson, entitled: , 1964 .

[8]  D. Tomlin,et al.  Self-diffusion in molybdenum , 1963 .

[9]  D. P. Gregory.  TEMPERATURE VARIATION OF FLOW STRESS IN BODY CENTERED CUBIC METALS , 1963 .

[10]  A. A. Johnson,et al.  Stage III recovery in neutron irradiated molybdenum and niobium , 1963 .

[11]  J. Nihoul.  The Recovery of Radiation Damage in Molybdenum , 1962, 1962.

[12]  P. Lucasson,et al.  Variation of Radiation Damage Parameters in Metals , 1962 .

[13]  P. Lucasson,et al.  PRODUCTION AND RECOVERY OF ELECTRON-INDUCED RADIATION DAMAGE IN A NUMBER OF METALS , 1962 .

[14]  R. Sizmann,et al.  Reaktionskinetische Analyse der Erholung von kaltverformtem Nickel im Temperaturgebiet 0— 300° C , 1962 .

[15]  W. Heller.  Quantum effects in diffusion: Internal friction due to hydrogen and deuterium dissolved in α-iron , 1961 .

[16]  M. W. Thompson.  The damage and recovery of neutron irradiated tungsten , 1960 .

[17]  M. Makin,et al.  THE MECHANICAL PROPERTIES OF IRRADIATED NIOBIUM , 1959 .

[18]  J. Adam,et al.  MEASUREMENTS OF UNIT CELL AND PHYSICAL DIMENSION CHANGES OF MOLYBDENUM AFTER NEUTRON IRRADIATION , 1958 .

[19]  M. W. Thompson,et al.  IRRADIATION DAMAGE AND RECOVERY IN MOLYBDENUM AND TUNGSTEN , 1958 .

[20]  T. Waite,et al.  Theoretical Treatment of the Kinetics of Diffusion-Limited Reactions , 1957 .

[21]  D. G. Martin.  The annealing of point defects in cold-worked molybdenum , 1957 .

[22]  J. Brinkman,et al.  Electrical Resistivity Study of Lattice Defects Introduced in Copper by 1.25-Mev Electron Irradiation at 80°K , 1956 .

[23]  A. Overhauser.  Isothermal Annealing Effects in Irradiated Copper , 1953 .

[24]  J. Marx,et al.  The internal friction of tantalum and columbium foils at ultrasonic frequencies , 1953 .

[25]  C. Ang.  Activation energies and diffusion coefficients of oxygen and nitrogen in niobium and tantalum , 1953 .