Samples of materials counted as perspective ones for use in the first-wall and construction elements in nuclear fusion reactors (FRs) with magnetic and inertial plasma confinement (W, Ti, Al, low-activated ferritic steel 'Eurofer' and some alloys) were irradiated in the dense plasma focus (DPF) device 'Bora' having a bank energy of 5 kJ. The device generates hot dense (T ∼ 1 keV, n ∼ 10 19 cm −3 ) deuterium plasma, powerful plasma streams (v ∼ 3×10 7 cm s −1 ) and fast (E ∼ 0.1 . . . 1.0 MeV) deuterons of power flux densities q up to 10 10 and 10 12 W cm −2 correspondingly. 'Damage factor' F = q × τ 0.5 ensures an opportunity to simulate radiation loads (predictable for both reactors types) by the plasma/ion streams, which have the same nature and namely those parameters as expected in the FR modules. Before and after irradiation we provided investigations of our samples by means of a number of analytical techniques. Among them we used optical and scanning electron microscopy to understand character and parameters of damageability of the surface layers of the samples. Atomic force microscopy was applied to measure roughness of the surface after irradiation. These characteristics are quite important for understanding mechanisms and values of dust production in FR that may relate to tritium retention and emergency situations in FR facilities. We also applied two new techniques. For the surface we elaborated the portable x-ray diffractometer that combines x-ray single photon detection with high spectroscopic and angular resolutions. For bulk damageability investigations we applied an x-ray microCT system where x-rays were produced by a Hamamatsu microfocus source (150 kV, 500 µA, 5 µm minimum focal spot size). The detector was a Hamamatsu CMOS flat panel coupled to a fibre optic plate under the GOS scintillator. The reconstruction of three-dimensional data was run with Cobra 7.4 and DIGIX CT software while VG Studio Max 2.1, and Amira 5.3 were used for segmentation and rendering. We have also provided numerical simulation of the fast ion beam action. The paper contains results on the investigations of modifications of the elemental contents, structure and properties of the materials.

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The (DC-GDPAU) is a DC glow discharge plasma experiment that was designed, established, and operated in the Physics Department at Ain Shams University (Egypt). The aim of this experiment is to study and improve some properties of a printed circuit board (PCB) by exposing it to the plasma. The device consists of cylindrical discharge chamber with movable parallel circular copper electrodes (cathode and anode) fixed inside it. The distance between them is 12 cm. This plasma experiment works in a low-pressure range (0.15-0.70 Torr) for Ar gas with a maximum DC power supply of 200 W. The Paschen curves and electrical plasma parameters (current, volt, power, resistance) characterized to the plasma have been measured and calculated at each cm between the two electrodes. Besides, the electron temperature and ion density are obtained at different radial distances using a double Langmuir probe. The electron temperature (KT e) was kept stable in range 6.58 to 10.44 eV; whereas the ion density (n i) was in range from 0.91 × 10 10 cm −3 to 1.79 × 10 10 cm −3. A digital optical microscope (800×) was employed to draw a comparison between the pre-and after effect of exposure to plasma on the shaping of the circuit layout. The experimental results show that the electrical conductivity increased after plasma exposure, also an improvement in the adhesion force in the Cu foil surface. A significant increase in the conductivity can be directly related to the position of the sample surfaces as well as to the time of exposure. This shows the importance of the obtained results in developing the PCBs manufacturing that uses in different microelectronics devices like those onboard of space vehicles.

The main purpose of this work is to use a low-cost DC plasma discharge to enhance the material properties. The source of the DC glow discharge plasma was the Batorm device. By using a low-pressure argon gas, the best operating conditions of the plasma were obtained at a pressure [Formula: see text] and a breakdown voltage of 160 V. Electrical parameters of the plasma have been experimentally estimated at two different pressures [Formula: see text] and [Formula: see text]. Tantalum material has been chosen to be treated along this work due to its great importance in industry. In addition, it is used as a cathode for the ion source inside the Egyptian cyclotron at the Egyptian Atomic Energy Authority (EAEA). A U-shaped tantalum sample, exactly like the cyclotron filament, was exposed to plasma created from [Formula: see text] and 250 V for 30 min. At these low conditions, the obtained results were promising where the surface treatment of the sample caused cleaning and increased its hardness.