A unique red calcite generation, which fills fractures/cavities, is hosted by Mesozoic carbonates in the Transdanubian Range, Hungary. Solid inclusions are located along growth zones of calcite. Hematite, the most abundant solid inclusion, gives the red colour of it. Outcrop‐scale geometry, mineralogical features and detrital mineral assemblage (hematite, gibbsite, goethite, kaolinite, smectite, illite, Cr‐spinel, monazite, xenotime, zircon, apatite and Ti‐oxide) of calcite precipitates suggest strong correlation between the calcite and nearby karst bauxite deposits. Fluid inclusion petrography and microthermometry (T < 50°C; salinity from 0 to 0.17 NaCl eq. w%) of primary fluid inclusions, and the stable isotope trend of the calcite, following the meteoric water line, clearly indicate vadose and phreatic meteoric origin in a near‐surface karst system. The late Cretaceous to mid‐Eocene unconformity‐related cavity‐filling deposits occur close to the surface; indicating that the most recent Quaternary exhumation re‐exposed those surfaces that existed at the time of calcite mineralization. Thus, red calcite precipitates are interpreted as being speleothems, vestiges of the subterranean part of the pre‐Middle Eocene karst. The infiltrated, fine bauxite particles enclosed by the calcite are the witnesses of the once areally extensive pre‐Middle Eocene bauxitic blanket that became partially eroded by the time of the deposition of the cover beds. Red calcite when found in core samples may provide good evidence on bauxite formation associated with the overlying unconformity, even if it was later removed by erosion. Therefore, presence or absence of red calcite may be used as distinguishing criteria between karst episodes with or without bauxite formation.
The paper presents some research results in the field of NiTi shape memory alloys made through powder metallurgy techniques. These techniques allow the obtaining of materials with savings of energy and time due to use of NiTi heat formation for the material synthesis. Ni-Ti, Ni-Ti-Fe and Ni-Ti-Cu alloys were performed by self propagation high temperature synthesis, starting from elemental powders. From the mixtures of powders with corresponding chemical c~mpositions were made green compacts by cold pressing WIth 400, 500 and 600 MPa which were then synthetized at 950, 1000 and 1050°C for 1 hour, in argon atmosphere.The obtained materials were investigated in order to detect the phase formation and to evidence the microstructural aspects. The martensitic transformation was evidenced by differential scanning calorimetry. As synthetised materials it were shown that only the Ni-Ti-Cu materials exhibits shape memory effects.
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