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The σ-T and dσ/dT-T curves of the FeCuNbSiB amorphous alloy, which are the relationship between "apparent weight loss" and temperature, are investigated by magnetic thermogravimetry analysis (MTGA) technique. It is found that the crystallization process of the samples can be divided into five stages. The studies of samples annealed in the temperature range of 480-610 °C for 1 h show that when the annealing temperature (Ta) is lower than 540 °C, the quantity of nanocrystalline α-Fe(Si) phase increases evidently with Ta, and the Curie temperature (TC) of residual amorphous phase also increases linearly with Ta, i.e., TC=0.52Ta+91.7 °C, with correlation coefficient γ=0.98. The variation of volume fraction of α-Fe(Si) nanocrystalline phase or residual amorphous phase with Ta is measured.

Hot band of a continuous cast AA 2037 Al alloy was annealed at different temperatures ranging from room temperature to 500℃ for 3h. Vacancy-solute interaction and precipitates in the hot band samples during annealing were investigated by positron annihilation techniques, coincidence Doppler broadening (CDB) of positron annihilation radiation and positron lifetime spectroscopy, and other methods. The experimental results indicated that there existed V-Cu and V-Cu-Mg complexes at room temperature. At 200℃, positron mean lifetime shows a peak value because of the formation of semicoherent particles. The characteristic shape of Mn was observed in the CDB ratio curve, which indicated the formation of V-Mg-Mn complexes or the existence of Mn clusters in the semicoherent particles. Above 250℃, coarsening and dissolution of semicoherent particles resulted in the decrease of mean lifetime and disappearance of the Mn signal, but the Cu signal increased clearly with annealing temperature. After 350℃, the Cu signal tended to saturation, which reflected that the Cu dissolved might agglomerate and cluster with vacancies during cooling the sample to room temperature, while new increase of mean lifetime might be attributed to the formation of incoherent phase, which was verified by DSC curve.

The interaction between hydrogen and defects in annealed,473K tempered and cold-rolled nickel samples has been investigated by positron lifetime and Doppler broadening measurements.Experimental results show that there has been no effect of hydrogen-charging on the nickel samples containing only dislocations,while in the samples containing vacancies the effect was evident.A long-lifetime component appeared for the latter,which may indicate that the hydrogen-vacancy composite is also the center of vacancy agglomeration.

Variation of S-parameter with the strain (S-ε curve) under different strain rate are investigated by combining Doppler broadening measurement with slow tensile test. Experimental results are as follows:1. Under slow strain rate, the S-ε curve in high purity iron does not tend to saturation. The slower the strain rate is, the more evident the "non-saturation phenomenon".2. Variations of S-ε curve with strain rate are attributed to the different configuration of dislocation distribution under different strain rates.3. As high purity iron is deformed, the increment of S-parameter depends not only on dislocation density but also on vacancy concentration, and we attibute the so called "non-saturation phenomenon" of S-ε curve to the strain induced vacancies.

The interaction between hydrogen atoms with defects in coldrolled nickel is investigated by Doppler broadening measurement. Experimental results show that the S-parameter in cold-rolled-hydrogen-charged nickel increases as compared with that of hydrogen-free cold-rolled nickel. And the increament of S-parameter depends on vacancy concentration, being almost independent of dislocation density. It is suggested that hydrogen atoms can act as centers of vacancy agglomeration, leading to the formation of vacancy cluster.