Thin structure of steel St52, 3N and possible reasons of defect of large-capacity billets AT "YURMASH"

Electron-microscopic and x-ray investigations of structurally-phase and intense-deformed condition of material made of defective and conditional forged billet at «Yurmash» have been carried out. It is ascertained that in steel made from the defective forged piece the fraction of perlite is 1,5...2 times higher and lamellar perlite prevails. Local long-range tensions in both conditions of material are commensurable with fluidity limit. The content of sulfides is considerably higher in the steel made from the defective billet. They are located in the body of ferrite grains and along the interfaces. In the material made from the conditional forging they are located only inside of grains. The scalar density of dislocations in ferrite grains and in ferrite layers of perlite of the defected billet is one and a half time higher than in conditional metal. All the totality of the listed above circumstances allows stating that the main cause of cracking of large-capacity billets made of steel St52, 3N is not a full conformity of the chemical compound to branded requirements

Development and Study of Hard-Facing Materials on the Base of Heat-Resisting High-Hardness Steels for Plasma-Jet Hard- Facing in Shielding-Doping Nitrogen Atmosphere

The authors develop hard-facing materials on the base of heat-resisting highhardness steels for plasma-jet hard-facing in nitrogen atmosphere for manufacturing parts of mining and metallurgic equipment which significantly simplify the production process and effect a saving when producing bimetallic parts and tools

Developing and Studying the Methods of Hard-Facing with Heat-Resisting High-Hardness Steels

The authors develop the methods of hard-facing of mining-metallurgic equipment parts with heat-resisting high-hardness steels on the base of plasma-jet hard-facing in the shielding-alloying nitrogen atmosphere

Optimizing Technological Parameters of the Reduction Processes in Treating Steels in a Ladle Furnace

This work reports the possible development of reduction processes when treating the molten metal and slag using a ladle furnace under conditions of intensive stirring with an inert gas. The industrial data have been received, confirming the possibility of decreasing the concentration of ferrous and manganese oxides in the slag and stabilizing the contents of manganese and silicon in the metal

Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66)

Optimizing Technological Parameters of the Reduction Processes in Treating Steels in a Ladle Furnace

This work reports the possible development of reduction processes when treating the molten metal and slag using a ladle furnace under conditions of intensive stirring with an inert gas. The industrial data have been received, confirming the possibility of decreasing the concentration of ferrous and manganese oxides in the slag and stabilizing the contents of manganese and silicon in the metal

Development and Study of Hard-Facing Materials on the Base of Heat-Resisting High-Hardness Steels for Plasma-Jet Hard- Facing in Shielding-Doping Nitrogen Atmosphere

The authors develop hard-facing materials on the base of heat-resisting highhardness steels for plasma-jet hard-facing in nitrogen atmosphere for manufacturing parts of mining and metallurgic equipment which significantly simplify the production process and effect a saving when producing bimetallic parts and tools

Extraction of Chromium from Carbon Ferrochromium Residual Wastes

This work reports the problem of processing residual wastes after producing carbon ferrochrome by recycling dust using a hydrometallurgical method with the purpose of extracting the basic component - chromium. The X-ray diffraction analysis results, chemical and granulometric compositions of dust from the carbon ferrochrome production are given. The method for the production of chemical-enrichment concentrate (CEC) by processing ferrous dust is described, with obtaining a middling product - sodium mono-chromate with its further reduction to chromium hydroxide, followed by autoclave leaching, and resulting in the production of chemically enriched chrome concentrate. The plant used for autoclave leaching and filtering is schematically depicted. The smelting process of metallic chromium using the ladle aluminothermic method is described

Easy-plane to easy-axis anisotropy switching in a Co(ii) single-ion magnet triggered by the diamagnetic lattice

Single ion magnets SIMs with large magnetic anisotropy are promising candidates for realization of single molecule based magnetic memory and qubits. Creation of materials with magnetically uncoupled spatially separated SIMs requires dilution in a diamagnetic matrix. Herein, we report that progressive dilution of paramagnetic Co II by diamagnetic Zn II in the SIM [CoxZn 1 amp; 8722;x piv 2 2 NH2 Py 2], x 1 0 beyond a threshold of 50 reveals an abrupt structural change, where the distorted tetrahedral Zn coordination structure is superimposed on the remaining Co ions, which were initially in a distorted octahedral environment. Dilution induced structure modification switches the magnetic anisotropy from easy plane D 36.7 cm amp; 8722;1 to easy axis type D amp; 8722;23.9 cm amp; 8722;1 , accompanied by a fivefold increase of the magnetic relaxation time at 2 K. Changes of the static and dynamic magnetic properties are monitored by electron paramagnetic resonance spectroscopy and AC susceptibility measurements. Complementary quantum chemical ab initio calculations quantify the influence of structural changes on the electronic structure and the magnetic anisotropy. Thus, magnetic dilution hits two goals at once, the creation of isolated magnetic centres and an improvement of their SIM propertie