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In order to be able to use intermetallic titanium aluminide in industrial applications, a quick and affordable method of quantitatively analysing their microstructures is required. In the presented work it was able to demonstrate on a powder metallurgical manufactured TNM™ alloy of nominal composition Ti-43.5Al-4Nb-1Mo-0.1B (at.%), that by electrolytic-polishing and colour etching a quick and cost effective quantitative microstructural analysis may be carried out via light-optical microscopic images. In doing so, the phase fractions and microstructural constituents of the various types of microstructures present are determined using complementary analysing techniques. Both light-optical and scanning electron microscopic images were captured from each of three different types of microstructures. These were then quantitatively evaluated using an image analysis program. The results were compared with those obtained from X-ray diffraction experiments. The possibilities and limits of the quantitative phase evaluation of light-optical microscopic images of colour etched microstructures are also explained and their relationship to the choice of parameters used for the colour etching and electro-polishing operations discussed.

AlxCr1−x composite cathodes with Al contents of x = 0.75, 0.5 and 0.25 were exposed to cathodic arc plasmas in Ar, N2 and O2 atmospheres and their erosion behaviour was studied. Cross-sectional analysis of the elemental distribution of the near-surface zone in the cathodes by scanning electron microscopy revealed the formation of a modified layer for all cathodes and atmospheres. Due to intermixing of Al and Cr in the heat-affected zone, intermetallic Al-Cr phases formed as evidenced by X-ray diffraction analysis. Cathode poisoning effects in the reactive N2 and O2 atmospheres were non-uniform as a result of the applied magnetic field configuration. With the exception of oxide islands on Al-rich cathodes, reactive layers were absent in the circular erosion zone, while nitrides and oxides formed in the less eroded centre region of the cathodes.

Abstract. Porosity and permeability are essential parameters for reservoir rocks. Techniques developed for conventional reservoir rocks characterized by large pores, cannot be applied to study gas shales. Therefore, high resolution techniques are increasingly used to determine reservoir quality of shale gas plays. Within the frame of the recent study, Upper Visean black shales ("Rudov Beds") from the Dniepr-Donets-Basin (DDB, Ukraine) were characterized by X-ray diffraction, conventional SEM imaging and FIB/BIB-SEM.According to SEM and FIB/BIB-SEM data, nanopores are not abundant in primary macerals (e.g., vitrinite) even in overmature rocks, whereas they develop within secondary organic matter (bitumen) formed mainly at gas window maturity. Frequently occurring sub-micrometre porosity, probably related to gas generation from bituminous organic matter, was detected within mudstones at a vitrinite reflectance > 2.0 % Rr. However, such pores have also been detected occasionally in solid bitumen at oil window maturity (0.9 % Rr). Authigenic nanoscale clay minerals and calcite occur within pyrobitumen at gas window maturity.Furthermore, Rudov Beds can be subdivided into mineralogical facies zones by SEM imaging and X-ray diffraction. A basin-centred, brittle siliceous facies is most likely caused by increased contribution from deeper water radiolaria and is separated from a marginal clayey and carbonate-rich facies.

The European Union, Japan, USA, the Russian Federation, China, and South Korea have decided in 2005 to construct the International Thermonuclear Experimental Reactor (ITER) in Cadarache, France. With ITER the feasibility shall be demonstrated to generate 500MW by nuclear fusion of Deuterium (D) and Tritium (T) to Helium (He) and neutrons. In ITER a set of superconducting magnets confines a D-T plasma at temperatures exceeding 100 MK corresponding to a thermal energy of 10 keV in a doughnut-shaped vacuum vessel. So-called plasma facing components (PFC) are installed inside the stainless steel vacuum vessel for its protection. The PFC are designed to absorb the heat flux from the plasma by active cooling with pressurized water in the presence of a considerable flux of 14 MeV neutrons, which carry about 80% of the energy surplus generated in a D-T fusion reaction. The erosion at the surface of the PFC has to be kept at a low level, in order not to cool the plasma by the ionisation of particles released into it. This is achieved by armouring the plasma facing surface with Be, C or W.In the divertor, which is located at the bottom of the ITER vacuum vessel, the plasma facing components are designed to absorb heat flux loads of up to 20 MW/m 2 , [1] which is COMMUNICATIONS