Phase transformations in a corrosion-resistant high-chromium nitrogen-bearing steel

The structure, phase composition, and mechanical properties of an austenitic corrosion-resistant high-chromium nitrogen-bearing (～0.5% N) steel are studied in the as-cast state and after homogenizing heat treatment (HT) followed by quenching. The main structural constituents of the as-cast steel are austenite and the σ phase (12%), which forms as an interdendritic metal during solidification, and δ ferrite and M ₂₃C₆-type chromium carbides are absent. Homogenizing HT at 1100–1200°C leads to the σ → γ transformation through the stage of the formation of intermediate δ ferrite via the restructuring of the tetragonal into the bcc lattice. Upon long-term homogenizing HT, the chromium concentration in ferrite decreases due to diffusion chromium redistribution and the δ → γ transformation takes place. The austenite in both the as-cast steel and the steel subjected to homogenizing HT followed by water quenching contains numerous (Cr, V)N nanoparticles. The twofold yield strength of this steel (～400 MPa) as compared to nitrogen-free 18Cr-10Ni-type steels can be explained by not only the solid-solution hardening of austenite by nitrogen but also by precipitation hardening.     

Probabilistic automata and simulation

Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 20–31, May–June, 1993.     

Direct bonding of silicon carbide wafers with a regular relief at the interface

The direct bonding of two oxide-free 6H-SiC(0001) silicon carbide single crystal wafers, one smooth and another bearing an artificial microscopic relief, has been studied. According to the X-ray topography data, the bonded surface fraction reaches 85% of the total area. The pattern of stress distribution at the interface is aperiodic, which is indicative of an inhomogeneous microroughness of the surface of bonded wafers.     

The Formation of Self-Organizing Organosilicone Layers on a Carbon Steel Surface and Their Effect on the Electrochemical and Corrosion Behavior of the Metal

Protection of Metals and Physical Chemistry of Surfaces - Adsorption on the carbon steel surface of vinyl trimethoxysilane and γ-aminopropyl triethoxysilane from aqueous solution is studied...     

Extraction of the carbon ion beam from the U-70 accelerator into beamline 4a using a bent single crystal

A beam of six-charged carbon ions with an energy of 24.8 GeV/nucleon is extracted from the U-70 synchrotron by means of a silicon crystal bent through 85 mrad. A total of 200000 particles are observed in beamline 4a upon forcing 10⁹ circulating ions to the crystal. The geometrical parameters, timing structure, and composition of the beam have been measured. It has been shown for the first time that, using a bent single crystal, an ion beam with required parameters can be extracted from the accelerator ring and formed for regular use in physics experiments.