INFLUENCE OF DOUBLE PHASE RECRYSTALLIZATION ON STRUCTURE FORMATION OF CARBON AND TOOL STEELS

The article presents research materials on thestructure and properties of hard-alloy coatings obtained in the process of casting products using gasified models. The composition and properties of steel were studied, as well as the hardness and microhardness of the surface and subsurface layers of castparts. The relative wear resistance of tests performed in laboratory and field conditions is analyzed. The final modes of heat treatment with double phase recrystallization for cast parts are carried out. It is shown that heat treatment with double phase recrystallization increases the wear resistance of hard-alloy coatings and finished products by 3-4 times.Keywords: gasified model Casting, hard-alloy coating, high-carbon steel, hardness and microhardness, microstructure, heat treatment with double phase recrystallization, abrasive wear resistance and durability

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Quantitative nano-characterization of heterogeneous catalysts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138361 ◽

1995 ◽

Vol 53 ◽

pp. 398-399

Author(s):

P.A. Crozier ◽

M. Pan

Keyword(s):

Heterogeneous Catalysts ◽

Low Dose ◽

Imaging Techniques ◽

Structural Features ◽

Catalyst Characterization ◽

New Developments ◽

Double Phase ◽

Phase Systems ◽

Dose Imaging

Heterogeneous catalysts can be of varying complexity ranging from single or double phase systems to complicated mixtures of metals and oxides with additives to help promote chemical reactions, extend the life of the catalysts, prevent poisoning etc. Although catalysis occurs on the surface of most systems, detailed descriptions of the microstructure and chemistry of catalysts can be helpful for developing an understanding of the mechanism by which a catalyst facilitates a reaction. Recent years have seen continued development and improvement of various TEM, STEM and AEM techniques for yielding information on the structure and chemistry of catalysts on the nanometer scale. Here we review some quantitative approaches to catalyst characterization that have resulted from new developments in instrumentation.HREM has been used to examine structural features of catalysts often by employing profile imaging techniques to study atomic details on the surface. Digital recording techniques employing slow-scan CCD cameras have facilitated the use of low-dose imaging in zeolite structure analysis and electron crystallography. Fig. la shows a low-dose image from SSZ-33 zeolite revealing the presence of a stacking fault.

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The Effects of Testing on Knowledge Structure Formation

PsycEXTRA Dataset ◽

10.1037/e502412013-763 ◽

2012 ◽

Author(s):

Milton E. Picklesimer ◽

Neil W. Mulligan

Keyword(s):

Structure Formation ◽

Knowledge Structure

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Cellular Automata Simulation of Dissipative Structure Formation in Heterogeneous Polymer Systems, Formation of Networks of a Dispersed Phase by Flocculation

Journal de Physique II ◽

10.1051/jp2:1996184 ◽

1996 ◽

Vol 6 (3) ◽

pp. 395-404 ◽

Cited By ~ 5

Author(s):

B. Wessling

Keyword(s):

Cellular Automata ◽

Structure Formation ◽

Dissipative Structure ◽

Dispersed Phase ◽

Polymer Systems ◽

Heterogeneous Polymer

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Social development of modern Russia: trends, risks, prospects

Voprosy Ekonomiki ◽

10.32609/0042-8736-2018-10-76-89 ◽

2018 ◽

pp. 76-89

Author(s):

E. M. Avraamova ◽

V. N. Titov

Keyword(s):

Middle Class ◽

Social Development ◽

Social Structure ◽

Structure Formation ◽

Resource Availability ◽

Social Dynamics ◽

Quantitative Estimation ◽

Resource Potential ◽

Institutional Conditions ◽

Resource Characteristics

The analysis of present-time directions in the study of social development has allowed to identify the resource approach as the most productive one which enables to assess social dynamics through the range of resource characteristics of different population groups and abilities of the relevant groups to apply development resources in the current economic and institutional conditions. Basing on the sociological survey conducted by ISAP RANEPA, the quantitative estimation of material and social recourses of the population has been made; integral values of the resource potential have been calculated as well. The issues of social structure formation are analyzed through the aspect of resource availability; the barriers of Russian middle-class enlargement are defined.

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Characteristics Of The Structure Formation Of Gypsum Binder Modified With Zinc Hydrosilicates

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2020.02.40-46 ◽

2020 ◽

pp. 40-46

Keyword(s):

Synergistic Effect ◽

Physicochemical Properties ◽

Structure Formation ◽

Silicic Acid ◽

Chemical Properties ◽

Crystal Formation ◽

Ability To Act ◽

Chemical Factors ◽

Sorption Characteristics

The authors' methodic for assessing the role of chemical and physic-chemical factors during the structure formation of gypsum stone is presented in the article. The methodic is also makes it possible to reveal the synergistic effect and to determine the ranges of variation of controls factors that ensure maximum values of such effect. The effect of a micro-sized modifier based on zinc hydro-silicates on the structure formation of building gypsum is analyzed and corresponding dependencies are found. It is shown that effects of influence of modifier on the properties of gypsum compositions are determined by chemical properties of modifier. Among the mentioned properties are sorption characteristics (which depend on the amount of silicic acid and its state) and physicochemical properties - the ability to act as a substrate during crystal formation. The proposed method can also be extended to other binding substances and materials. This article contributes to the understanding of the processes that occur during the structure formation of composites, which will make it possible to control the structure formation in the future, obtaining materials with a given set of properties.

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Study Of Structure Formation Of Organic-Mineral Compositions With Fibrous Filler By Electron Microscopy Method

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.12.41-47 ◽

2019 ◽

pp. 41-47

Keyword(s):

Electron Microscopy ◽

Structure Formation ◽

Mineral Composition ◽

Bending Strength ◽

Cement Stone ◽

Hydrated Cement ◽

Fibrous Filler ◽

Organic Mineral ◽

Microscopy Method ◽

Mineral Compositions

The article presents the study of processes of structure formation of cement stone and products of hardening of organic-mineral compositions with fibrous filler (shavings) by the electronic scanning microscopy method. It is established that the additive-free cement stone at the age of 28 days has a dense and homogeneous structure, consists of calcium hydro-silicates, Portlandite and calcite - newgrowths characteristic for cement systems. Cellulose fibers, which make up the bulk of the substance of shavings, are sufficiently active, which determines the high adhesion of the hydration products of the cement binder to their surface. It is shown that the introduction of shavings into the organo-mineral composition leads to inhibition of cement hydration processes. Organo-mineral compositions with different shavings content (two compositions) were analyzed. The first composition is characterized by a fairly dense structure, the cement stone consists of globular nanoscale nuclei of hydrosilicates, Portlandite and calcite. The second composition has a loose porous structure, cement stone consists of non-hydrated cement grains, newgrowths are represented by calcite and vaterite. The structure of the contact zone "osprey fiber-cement stone" in the organo-mineral composition of the first composition indicates a good adhesion of the filler surface with the phases of hydrated cement. The use of shavings as a fibrous filler (the first composition) increases the tensile and bending strength, as well as the wear resistance of organo-mineral compositions. The data obtained by scanning electron microscopy are confirmed by the results of studying the processes of structure formation of cement stone by quantitative x-ray phase analysis.

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