This article is dedicated to exploring the response of ceramic materials and glasses to a strong external impact and self-organization processes that take place at the same time. Out of the many strong external impacts, torsion under pressure is studied. Results of electron microscopy studies have been presented covering a number of brittle materials that differ significantly in terms of their nature. Structural evolution of ceramics and glass subjected to torsion under pressure is analyzed. Crystalline ceramics (quartz, rock crystal) and amorphous glass types (microscope, quartz) are used. Enhanced consolidation of ceramic powders due to torsion has been observed. It has been demonstrated that this enhancement is preconditioned by rotation of particles, their mutual collisions, disappearance of micro-projections, faceting of particles, and formation of particle aggregations leading to their cohesion. The behavior of particles in this case is identical to that of bulky bodies during their deformation. It has been demonstrated that resulting plates of consolidated ceramics contain a network of microcracks prone to branching. It is established that there exists a clear correlation between the shape of microcracks and the structural condition of ceramics. In case of the crystalline quartz, microcracks consist of rectilinear segments, while in case of the amorphous microscope glass, these will be thin curved microcracks. It has been found that HPT of the quartz glass results in the formation of a sandwich type structure: outer layers of the crystalline quartz and inner layer of the amorphous quartz glass. After etching, two types of microcracks are observed: with (outer layer) and without rectilinear segments (inner layer), respectively. The enhanced consolidation of the ceramics due to strong external impacts is primarily preconditioned by torsion. That's why HPT is a more efficient processing method of the ceramics compared, for example, with rolling, forging and their composition.
|Название основной публикации||BASIC PROBLEMS OF MATERIAL SCIENCE|
|Редакторы||Starostenkov M. D.|
|Издатель||Общество с ограниченной ответственностью "Научно-исследовательский центр "Системы управления"|
|ISBN (печатное издание)||978-5-7568-1265-7|
|Состояние||Опубликовано - 2018|