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Interaction between high-intensity pulsed ion beam (HIPIB) and a double-layer target with titanium film on top of aluminum substrate was simulated. The two-dimensional nonlinear thermal conduction equations, with the deposited energy in the target taken as source term, were derived and solved by finite differential method. As a result, the two-dimensional spatial and temporal evolution profiles of temperature were obtained for a titanium/aluminum double-layer target irradiated by a pulse of HIPIB. The effects of ion beam current density on the phase state of the target materials near the film and substrate interface were analyzed. Both titanium and aluminum were melted near the interface after a shot when the ion beam current density fell in the range of 100 A/cm2 to 200 A/cm2.

We report a modification method for ZrO2 thermal barrier coatings (TBCs) by high-intensity pulsed ion beam (HIPIB) irradiation. Based on the temporal and spatial distribution models of the ion beam density detected by Faraday cup in the chamber and the ions accelerating voltage, the energy deposition of the beam ions in ZrO2 is calculated by Monte Carlo method. Taking this time-dependent nonlinear deposited energy as the source term of two-dimensional thermal conduction equation, we obtain the temporal and spatial ablation process of ZrO2 thermal barrier coatings during a pulse time. The top-layer TBC material in thickness of about 0.2 μm is ablated by vaporization and the coating in thickness of 1 μm is melted after one shot at the ion current density of 200 A/cm2. This calculation is in reasonable agreement with those measured by HIPIB irradiation experiments. The melted top coat becoming a dense modification layer due to HIPIB irradiation seals the gaps among ZrO2 crystal clusters, and hence barrels the direct tunnel of oxygen.

The green and red up-conversion emissions centred at about 534, 549 and 663nm of wavelength, corresponding respectively to the 2H11/2 → 4I15/2, 4S3/2 → 4I15/2 and 4F9/2 → 4I15/2 transitions of Er3+ ions, have been observed for the Er3+-doped silicate glass excited by a 978nm semiconductor laser beam. Excitation power dependent behaviour of the up-conversion emission intensity indicates that a two-photon absorption up-conversion process is responsible for the green and red up-conversion emissions. The temperature dependence of the green up-conversion emissions is also studied in a temperature range of 296–673 K, which shows that Er3+-doped silicate glass can be used as a sensor in high-temperature measurement.

The presence of α-Fe(N), γ'-Fe4N and e-Fe2N1-x phases and the phase equilibrium between α-Fe(N) and γ'-Fe4N, and γ'-Fe4N and e-Fe2N1-x have been studied at low temperatures below 350°C, according to the binary Fe-N phase diagram calculated using the sublattice-compound energy model. The α-Fe(N), γ'-Fe4N and e-Fe2N1-x phases would be thermodynamically stable at the low temperatures. Thermodynamic phase equilibrium of the iron nitrides is supported by the experimental results, explaining the phase formation and its stability in the Fe-N system at low temperatures.