Gripping Prospective of Non-Shear Flows under High-Pressure Torsion.

The article presents a theoretical study of the regimes of high-pressure torsion (HPT) for which slippage of the deforming material on the interfaces with anvils is possible. The approach taken is a generalisation of the currently accepted view of the HPT process. It enables a rational explanation of its salient features and the effects observed experimentally.

Structure Refinement and Fragmentation of Precipitates under Severe Plastic Deformation: A Review.

During severe plastic deformation (SPD), the processes of lattice defect formation as well as their relaxation (annihilation) compete with each other. As a result, a dynamic equilibrium is established, and a steady state is reached after a certain strain value. Simultaneously, other kinetic processes act in opposite directions and also compete with each other during SPD, such as grain refinement/growth, mechanical strengthening/softening, formation/decomposition of solid solution, etc.

The Earth's Lithosphere Inspires Materials Design.

Structural patterns found in living organisms have long been inspiring biomimetic materials design. Here, it is suggested that a rich palette of patterns occurring in inanimate Nature, and especially in the Earth's lithosphere, could be not less inspirational for design of novel architectured materials. This materials design paradigm is referred to as lithomimetics and it is demonstrated that some of the patterns found in the lithosphere can be emulated by established processes of severe plastic deformation.

Mechanical Modelling of the Plastic Flow Machining Process.

A new severe plastic deformation process, plastic flow machining (PFM), was introduced recently to produce sheet materials with ultrafine and gradient structures from bulk samples in one single deformation step. During the PFM process, a part of a rectangular sample is transformed into a thin sheet or fin under high hydrostatic pressure. The obtained fin is heavily deformed and presents a strain gradient across its thickness.

The self-similarity theory of high pressure torsion.

By analyzing the problem of high pressure torsion (HPT) in the rigid plastic formulation, we show that the power hardening law of plastically deformed materials leads to self-similarity of HPT, admitting a simple mathematical description of the process. The analysis shows that the main parameters of HPT are proportional to β , with β being the angle of the anvil rotation. The meaning of the parameter is: = 0 for velocity and strain rate, = 1 for shear strain and von Mises strain, = for stress, pressure and torque ( is the exponent of a power hardening law).

Lymph Node Reaction to Cancer. (Immunohistochemical and Ultrastructural Study).

A total of 153 regional lymph nodes obtained from 50 patients, operated for gastric, lung, breast, colonic and cervical cancers, were studied. Immunohistochemical methods were used to detect different markers and enzymes (CD1, CD2, CD3, CD4, CD8, CD20, CD30, CD35, CD45, l light Ig chain, lysozyme (muramidase), a-1-antichymotrypsin, protein S100 and FVIIIR). Results indicate that failure of local immunity is explained by the followings: 1.