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A study of defect structure in (TiZrHfNbV)N coatings irradiated with 200 MeV high energy Xe14+ ions with different fluences by positron annihilation spectroscopy (PAS) was carried out. Positron lifetime studies showed that the vacancy-defects are the dominant defects type in investigated specimens. Although (TiZrHfNbV)N coatings were irradiated with high energy Xe+ ions with different fluences: 5 × 1011, 5 × 1012 and 5 × 1013 ions/cm2, no amorphous or intermetallic phase are detected.

Kinetic processes of nanoparticle formation by ion implantation was studied for the insulators of a-SiO 2 , LiNbO 3 , MgO · 2.4(Al 2 O 3 ) and PMMA, either by changing ion flux or by using a co-irradiation technique of ions and photons. Under Cu-implantation of 60 keV Cu − , nanoparticles spontaneously formed without thermal annealing, indicating radiation-induced diffusion of implants. The high-flux implantation caused instable behaviors of nanoparticle morphology in a-SiO 2 , LiNbO 3 and PMMA, i.e. enhanced atomic rearrangement or loss of nanoparticles. The spinel MgO · 2.4(Al 2 O 3 ) also showed nanoparticle precipitation at 60 keV, but the precipitation tendency is less than the others. Combined irradiation of 3 MeV Cu ions and photons of 2.3 eV or 3.5 eV indicates that the electronic excitation during ion implantation significantly enhances nanoparticle precipitation, greatly depending on photon energy and fluence. The selectivity for photons can be applied to control nanoparticle precipitation.

Spectra of ion-induced photon emissions (IIPE) of silica glass were measured during implantation of 3 MeV Cu ions at a constant flux of 3–10 μA/cm2 up to a fluence of 9×1016 ions/cm2. Three bands compose the IIPE spectra: a tail of the oxygen-deficient center band, the band of Cu+ ions at 2.27 eV and the band of non-bridging oxygen hole center at 1.89 eV. Intrinsic defects of silica glass contribute to the IIPE at the onset of irradiation only. At fluences higher than 5×1014 ions/cm2, the fluence dependence of the Cu+-band of IIPE represents (a) the accumulation of Cu solutes preceding the nanoparticle formation and (b) no change of Cu solute concentration during nanoparticle growth. The intensity of the Cu+-band is proportional to the total concentration of Cu solutes. The balance of Cu solutes and Cu nanoparticles is sensitive to the ion flux. The concentration of Cu solutes necessary for nanoparticle formation cannot be attained at fluxes higher than 10 μA/cm2.

Nanoparticles of titanium oxides have been fabricated by ablating a Ti target with pulsed CO2-laser deposition in Ar-diluted oxygen environments. The pulse energy and repetition rate of the CO2 laser (wavelength 10.6 μm) are 0.44 J/cm2 per pulse and 50 Hz, respectively. During the focused laser irradiates the Ti target, Ar and O2 gases are supplied into the irradiation chamber. The gas pressure is varied in a range of 1×103 to 1×105 Pa. The flow rates of Ar and O2 gases are adjusted in ranges of 75–83 and 3.3–8.3 cm3/s, respectively. Above 3×104 Pa, the laser irradiation creates nanosized spherical particles of titanium dioxide. The nanospheres are characterized by transmission electron microscopy (TEM) to be of the anatase type. Each nanoparticle consists of a single crystal or single-crystalline domains. The particle size slightly increased with increasing the gas pressure, irrespective of the flow rate. The results demonstrate that nanoparticles of anatase TiO2 are created by the reactive pulsed laser deposition (PLD).

In order to understand the spectral characteristics of ZnS: Sm nanocrystals, in which a novel optical memory effect has been observed, optical properties have been studied between 2 and 300 K for the samples prepared by a solution method. The broad fluorescence and excitation bands observed in the visible region are tentatively assigned to the transitions between the 4f 6 and 4f 5 5d states of Sm 2 + and also to the transitions of excitons bound to Sm 2+ . Temperature dependence of the intensity of the lowest-energy emission band and the dependence of its peak position on the excitation wavelength have been explained well by these assignments.

Recently, Japanese iron and steel companies have added a O 2 control system to their conventional combustion control systems for reheating furnaces in order to minimize O 2 content. Kimitsu Works of Nippon Steel Corporation developed a new, direct section-type 0 2 analyzer, an optimum multi-variable control system for multizone reheating furnaces, and an adaptive control system for soaking pits. As a result, fuel consumption in reheating furnaces of Kimitsu Works has been reduced by about 3%, and fuel consumption in the soaking pits has been reduced by about 5%. In addition, considerable reductions have been realized in the NOx content of waste gas and the amount of scale loss.

Summary By studying the mode shape animation based on the results of modal analysis, the dynamic rigidity of machine tool structures can be improved. This technique was successfully applied to a machining cell, an arm of automatic assembling machine and a conventional cylindrical grinder. Further, the application of advanced softwares can be used to predict the quantitative improvement in the dynamic rigidity. The examples on a vertical milling machine, an NC lathe and a surface grinder show effectiveness of the software approach in suppressing the chatter and improving the surface finish. Also the cutting test verified the predicted improvement.