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The annealing behaviour of C in the group IVa metal Hf has been studied in the previously uninvestigated temperature range 650–800°C using ion-beam techniques. Diffusion couples were created by ion implantation. The time evolution of the carbon profiles were monitored by the use of the Nuclear Resonance Broadening (NRB) technique. The linear Arrhenius plot extracted from the measurements indicates that the diffusivity of implanted C in polycrystalline h.c.p. a-Hf can be described by the activation energyQ=3.9±0.2 eV and the pre-exponential factor D0=(50±47120)×105 cm2/s. The implanted distributions were used to determine the solubility of C in a-Hf for the first time.

The diffusion of Al in the group IVa metals Zr and Hf has been studied for the first time in the temperature ranges 600°–800°C (Zr) and 750°–900°C (Hf) using ion-beam techniques. Diffusion couples were created by ion-implantation. The time-dependent diffusion profiles were monitored by the use of the Nuclear Resonance Broadening (NRB) technique. The linear Arrhenius plots extracted from the measured diffusivities indicate that the diffusivity of implanted Al in Zr and Hf can be described by the activation energyQ=2.9±0.2eV and 3.7±0.3eV and the pre-exponential factorD0=17±42cm2/s and 170±600cm2/s, respectively.

The diffusion of N in the group VI B metals Cr and W has been studied in the previously uninvestigated temperature ranges 300°–550 °C (Cr) and 600°–800 °C (W) using ion-beam techniques. Diffusion couples were created by ion-implantation. The timedependent diffusion profiles were monitored by the use of the Nuclear Resonance Broadening (NRB) technique. The linear Arrhenius plots extracted from the measured diffusivities indicate that the diffusivity of implanted N in Cr and W can be described by the activation energyQ=1.39±0.06 eV and 2.32±0.16 eV and the pre-exponential factorD0=(7.0±7.2)×10-4cm2/s and 4.3±8.3cm2/s, respectively. The solubilities of N in Cr and W from the implanted distributions were found to deviate from those obtained using conventional metallographical methods.

The diffusion of N in the group VB metals V and Nb has been studied in the previously uninvestigated temperature range 300–500 °C using ion-beam techniques. Diffusion couples were created by ion implantation. The time-dependent diffusion profiles were monitored by the use of the Nuclear Resonance Broadening (NRB) technique. New values for the solubility of N in Nb were obtained. The diffusion rates presented support recent observations of the diffusivity of interstitial impurities in body-centered cubic metals in which positive deviations from Arrhenius behaviour have been seen at high temperatures.

The annealing behaviour of C-, N-, Mg-, Al- and P-implanted Si and Ge has been investigated by the (p,?) resonance broadening method. In the cases of C- and Mg-implanted Ge, and N- and Al-implanted Si, fast out-diffusion and blocking of the implanted atoms at the sample surface was observed. Partial out-diffusion and blocking of nitrogen implanted in Ge took place. In the cases of Mg-implanted silicon and P-implanted germanium no blocking occurred and a decrease in the number of implanted atoms took place. In C-implanted Si retarded surface enrichment was observed, whereas in P-implanted Si clear diffusion into the bulk took place and no out-diffusion was observed.