INFLUENCE OF WARM ROLLING AND RECRYSTALLIZATION ANNEALING ON MECHANICAL AND METALLOGRAPHIC PROPERTIES OF THE SUPERALLOY N07080

Additional strengthening of superalloy N07080 described in this work was achieved by warm rolling. Control of the ratio of strength and ductile properties of the superalloy is possible by appropriate selection of the amount of warm deformation and the appropriate selection of the partial recrystallization temperature. In addition, recrystallization annealing makes it possible to equalize the grain size across the cross section of the warm rolled bars, which before recrystallization differ significantly in size in the central and peripheral parts of the bars.

Rb-Sr age of the riphean glauconites of the Kamov group (Baikit anteklise, Siberian platform)

A mineralogical and geochemical study was conducted and the Rb-Sr age of globular layered silicates (GPS) of the glauconite-illite series of the Dolgokta Formation from a parametric Chunkinskaya-282 drillcore was determined. The assessment of suitability of the mineral for geochronological purposes took into account the data of Mössbauer spectroscopy and modeling of the cation distribution in the GPS octahedral net. Mineralogical and crystalochemical characteristics indicate an epigenetic alteration of glauconite structure; therefore, its Rb-Sr isochronous age (1300 ± 7 Ma) is “rejuvenated” and reflects the stage of partial recrystallization. The 87Sr/86Sr ratio in dolomites of the Dolgokta and Kuyumba formations varies from 0.70602 to 0.72230, which confirms the epigenetic recrystallization. The model Rb-Sr age of glauconite, calculated taking into account the enrichment of radiogenic 87Sr, is within 1340-1400 Ma. The age estimate determines the upper limit of distribution of the Mesoproterozoic fossil Tappania, found in the Yurubchen and Dolgokta formations of the Baikit anteclise.