Kinetic Processes in Polydisperse Systems: Experience of Practical Approximation

2019 ◽  
Vol 814 ◽  
pp. 33-37
Author(s):  
Irina Garkina ◽  
Alexander Danilov
Keyword(s):  
Complex System ◽  
Composite Material ◽  
Composite Materials ◽  
Structure Formation ◽  
Analytical Methods ◽  
Building Materials ◽  
Parametric Identification ◽  
Kinetic Processes ◽  
Nonlinear Kinetic

Composite material is considered as a complex system with corresponding system attributes. The systematization of studies on the structure formation of composites is carried out to ensure the fundamentalization of building materials based on the use of analytical methods. The experience of using the linearization of kinetic processes in polydisperse systems is given. The most important cases are considered. Examples of parametric identification of a table-specified and nonlinear kinetic processes are given. The results were used in the development of special purpose composite materials.

scholarly journals Approximation of Functions in Multi-criterial Synthesis of Composite Materials

2021 ◽  
Vol 1203 (2) ◽  
pp. 022010
Author(s):  
Eugenia Budylina ◽  
Irina Garkina ◽  
Alexander Danilov
Keyword(s):  
Composite Materials ◽  
Complex Systems ◽  
Hierarchical Structure ◽  
Building Materials ◽  
Mathematical Structure ◽  
Parametric Identification ◽  
Generalized Polynomials ◽  
The Hierarchical Structure ◽  
Research Procedure ◽  
Kinetic Processes

Abstract A prerequisite for the synthesis of composite materials as complex systems is the principles of the control paradigm of Peace and the effectiveness of mathematics (for any reality and any given (not absolute) accuracy, there is a mathematical structure that describes this reality with this accuracy; the converse is also true (homomorphism, arbitrarily close to isomorphism between reality and mathematical structures)).The proposed methodology for managing the identification process (design of composites) includes the process of human choice: the probabilistic nature of the control; the main reason for the inadequacy of a purely analytical research procedure. Here, the optimization of the control of the properties of the composite is carried out experimentally on the model as a result of the approximation of the response function: not the generalized functional is approximated, but the particular criteria of which it consists. The development of composite materials is carried out on the basis of evaluating the parameters of the formation of operational properties. The parameters of each of the kinetic processes of the formation of the physical and mechanical characteristics of the material were taken as particular criteria. Kinetic processes are asymptotic for the composites under study and contain extremum and inflection points. A method is used to approximate multidimensional table-defined functions by generalized polynomials of a particular form. In the parametric identification of kinetic processes, their parameters are considered basic. Approximating models of the main properties are presented. Vector optimization of properties (selection of recipes, technologies and methods of material quality control) is carried out by overcoming ambiguities of goals using linear convolution, introducing benchmarks, building Pareto sets, etc. The expediency of using a systematic approach (the hierarchical structure of properties and the hierarchical structure of the composite proper) to the design of building materials as complex systems is shown. The research results are introduced as prototypes of new identification systems in the development of composite materials with adjustable structure and properties, in contrast to the replication of reference applied developments of identification theory in various industries.

scholarly journals Implementation of Contact-Condensation Hardening Theory Mechanisms when Forming Building Composites

2020 ◽  
Vol 24 (1) ◽  
pp. 90-102
Author(s):  
M. P. Stepanova ◽  
O. A. Sotnikova
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Structure Formation ◽  
Building Materials ◽  
Raw Materials ◽  
Raw Material ◽  
Material Base ◽  
Resource Saving ◽  
The Impact ◽  
Contact Condensation

Purpose of research is to study cheaper composite materials for building structures such as cement-free ones without heat treatment, which will undoubtedly allow finding their application in building industry. To achieve this goal it is necessary to identify patterns of structure formation of clinker-free contact condensation hardening composite materials in which portlandite crystals act as a matrix, and the physicochemical active component of natural origin acts as a filler.Methods. In accordance with the purpose set, one of the main tasks of the work was to be solved; it involved study-ing the patterns of structure formation of contact-condensation hardening systems relying on the basic principles of materials science, which include studying the influence of the composition, structure and state of the starting com-ponents on the properties of a composite material. In this work, we studied the role of the physicochemical activity of raw materials and the possibility of ‘combining’ a portlandite matrix with filling mechano-physicochemical active raw materials capable of producing new structures. To form the composite material, a compaction pressing technique at elevated specific pressures was used, which made it possible to implement the mechanisms of contact condensation technology of structure formation. The formation of physicochemical bonds of portlandite and aluminosilicate filler of various types is also possible with certain ratios of their mass fractions and V/I ratios the optimization of which was one of our objectives.Results. The result of this work is to assess the impact of raw material characteristics and technology parameters on the properties of the resulting material, namely, the improvement of the compacting pressure and the amount of filler when getting a compacted composite.Conclusion. The development of a technology of producing clinker-free contact condensation composites based on portlandite with aluminosilicate filler will expand the raw material base of local building materials, reduce their cost and energy consumption, that is, solve key issues of resource saving in the building materials production.

scholarly journals Particularities of structure formation of aluminum-copper composite materials manufactured by casting technology

2020 ◽  
pp. 116-121
Author(s):  
V. A. Kalinichenko ◽  
A. S. Kalinichenko ◽  
S. V. Grigoriev
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Structure Formation ◽  
Matrix Material ◽  
Matrix Alloy ◽  
Alloying Elements ◽  
Casting Technology ◽  
The Matrix ◽  
Reinforcing Material ◽  
Copper Composite

To create friction pairs operating in severe working conditions, composite materials are now increasingly used. Composite materials obtained with the use of casting technologies are of interest due to the possibility to manufacture wide range of compositions at low price compared to powder metallurgy. Despite the fact that many composite materials have been sufficiently studied, it is of interest to develop new areas of application and give them the properties required by the consumer. In the present work the composite materials on the basis of silumin reinforced with copper granules were considered. Attention was paid to the interaction between the matrix alloy and the reinforcing phase material as determining the properties of the composite material. The analysis of distribution of the basic alloying elements in volume of composite material and also in zones of the interphases interaction is carried out. The analysis of the possibility of obtaining a strong interphase zone of contact between the reinforcing component and the matrix material without significant dissolution of the reinforcing material is carried out.

scholarly journals Development of quality functionals of kinetic processes for the synthesis of composite materials with specified parameters of structure and properties

2020 ◽  
Vol 224 ◽  
pp. 02019
Author(s):  
A Bormotov
Keyword(s):  
Mathematical Method ◽  
Composite Materials ◽  
Polymer Composites ◽  
Structure Formation ◽  
High Viscosity ◽  
Transient Processes ◽  
Structure And Properties ◽  
Mathematical Methods ◽  
Kinetic Processes ◽  
Necessary And Sufficient

The processes of structure formation and features of polymer composites with special properties are investigated, the main kinetic processes that have a decisive influence on the structure formation and properties of polymer composites are identified. The expediency of considering kinetic (transient) processes as a necessary and sufficient sign of the structure formation of a thermosetting is substantiated. A mathematical method for the synthesis of polymer composite materials of increased density using the quality functionals of kinetic (transient) processes is proposed. The proposed mathematical methods and models allow to effectively solve the problem of plasticization and modification of high-viscosity polymers, as well as to carry out multi-criteria synthesis of composite materials with strictly specified parameters of structure and properties using the quality functionals of kinetic (transient) processes.

An Assessment of the PCM/Timber Composite in Buildings

2014 ◽  
Vol 604 ◽  
pp. 227-231 ◽  
Author(s):  
Janis Kazjonovs ◽  
Jana Vecstaudz ◽  
Janis Locs ◽  
Diana Bajare ◽  
Aleksandrs Korjakins
Keyword(s):  
Computer Simulation ◽  
Composite Material ◽  
Composite Materials ◽  
Building Materials ◽  
Material Behavior ◽  
Thermal Mass ◽  
Cooling Loads ◽  
Modeling Study

This paper reviews a modeling study on PCM/timber composite materials and their incorporation in building materials, particularly in passive applications. Commercially available paraffin PCMs (RT21 and RT27) were incorporated in timber for increasing its thermal mass. In order to evaluate PCM/timber composite material behavior in building, computer simulation was performed. The obtained results showed that by using this technique it is possible to increase the thermal mass and reduce cooling loads in summer conditions.

scholarly journals MECHANISMS OF STRUCTURE FORMATION IN NONFIRED COMPOSITE BUILDING MATERIALS

2018 ◽  
Vol 8 (4) ◽  
pp. 44-49
Author(s):  
Anatoly A. ABRAMENKO ◽  
Vitaly V. VOLKOV ◽  
(SOLOVYEVA) Ekaterina A. BRITVINA
Keyword(s):  
Composite Materials ◽  
Structure Formation ◽  
Building Materials ◽  
Materials Science ◽  
Dispersed Systems ◽  
Initial Strength ◽  
Physicochemical Processes ◽  
The Cost

Currently one of the tasks of materials science is to fi nd ways to reduce the cost of building materials. Studies have shown that the initial strength of the starting components does not aff ect the properties of the material. The article presents a study of the physicochemical processes occurring on the surface of dispersed components, the infl uence of the thickness of water fi lms on the strength of the fi nal material. The interdependence between the area of the endo-eff ects of thermograms and the strength of the materials obtained is considered. A model of interaction in dispersed systems is proposed, which allows one to infl uence the structure formation of composite materials in a targeted manner. Research is aimed at studying the patt erns of physicochemical processes on the surface of fi ne particles, the understanding of which allows us to predict, and subsequently set the properties of the materials obtained.

Environmental Compatibility of Carbon Reinforced Concrete: Irrigated Construction Elements

2019 ◽  
Vol 809 ◽  
pp. 314-319 ◽  
Author(s):  
Lia Weiler ◽  
Anya Vollpracht
Keyword(s):  
Heavy Metal ◽  
Composite Material ◽  
Reinforced Concrete ◽  
Composite Materials ◽  
Building Materials ◽  
Outdoor Exposure ◽  
Leaching Behavior ◽  
Environmental Compatibility ◽  
Materials Research ◽  
Harmful Substances

To foster a sustainable deployment of the innovative composite material ‘carbon concrete composite’ in the building sector, it is necessary to ensure its resource efficiency and environmental compatibility. The Institute for Building Materials Research of the RWTH Aachen University is therefore investigating the leaching behavior of this material, especially for the case of irrigated façade elements. Laboratory and outdoor exposure tests are run to determine and assess the heavy metal and trace element emissions by leaching. Feasible interconnections between laboratory and outdoor examinations can be used to develop a faster testing of future composite materials. Current results show no critical release of environmental harmful substances from carbon concrete composite.

Study of the Composite Materials Optimal Structure Containing a Hollow Aluminum and Silica Microsphere Dependence on Humidity

2020 ◽  
Vol 12 ◽  
Author(s):  
Alexandra Atyaksheva ◽  
Yermek Sarsikeyev ◽  
Anastasia Atyaksheva ◽  
Olga Galtseva ◽  
Alexander Rogachev
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Strength Function ◽  
Theory And Practice ◽  
Optimal Structure ◽  
Optimal Size ◽  
Structure And Properties ◽  
Power Functions ◽  
Silica Microsphere ◽  
Heat Engineering

Aims:: The main goals of this research are exploration of energy-efficient building materials when replacing natural materials with industrial waste and development of the theory and practice of obtaining light and ultra-light gravel materials based on mineral binders and waste dump ash and slag mixtures of hydraulic removal. Background.: Experimental data on the conditions of formation of gravel materials containing hollow aluminum and silica microsphere with opportunity of receipt of optimum structure and properties depending on humidity with the using of various binders are presented in this article. This article dwells on the scientific study of opportunity physical-mechanical properties of composite materials optimization are considered. Objective.: Composite material contains hollow aluminum and silica microsphere. Method.: The study is based on the application of the method of separation of power and heat engineering functions. The method is based on the use of the factor structure optimality, which takes into account the primary and secondary stress fields of the structural gravel material. This indicates the possibility of obtaining gravel material with the most uniform distribution of nano - and microparticles in the gravel material and the formation of stable matrices with minimization of stress concentrations. Experiments show that the thickness of the cement shell, which performs power functions, is directly related to the size of the raw granules. At the same time, the thickness of the cement crust, regardless of the type of binder, with increasing moisture content has a higher rate of formation for granules of larger diameter. Results.: The conditions for the formation of gravel composite materials containing a hollow aluminosilicate microsphere are studied. The optimal structure and properties of the gravel composite material were obtained. The dependence of the strength function on humidity and the type of binder has been investigated. The optimal size and shape of binary form of gravel material containing a hollow aluminosilicate microsphere with a minimum thickness of a cement shell and a maximum strength function was obtained. Conclusion.: Received structure allows to separate power and heat engineering functions in material and to minimize the content of the excited environment centers.

Hierarchical ZSM-22/PHTS composite material and its hydro-isomerization performance in hydro-upgrading of gasoline

2021 ◽  
Author(s):  
Jiyuan Fan ◽  
Chengkun Xiao ◽  
Jinlin Mei ◽  
Cong Liu ◽  
Aijun Duan ◽  
...  
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Impregnation Method ◽  
Molar Ratios

CoMo series catalysts based on ZSM-22/PHTS (ZP) composite materials with different SiO2/Al2O3 molar ratios were prepared via the impregnation method. The properties of the ZP material and the corresponding catalysts...

scholarly journals Acoustic Emission and K-S Metric Entropy as Methods for Determining Mechanical Properties of Composite Materials

Sensors ◽  
2020 ◽  
Vol 21 (1) ◽  
pp. 145
Author(s):  
Lesław Kyzioł ◽  
Katarzyna Panasiuk ◽  
Grzegorz Hajdukiewicz ◽  
Krzysztof Dudzik
Keyword(s):  
Mechanical Properties ◽  
Acoustic Emission ◽  
Composite Material ◽  
Composite Materials ◽  
Testing Machine ◽  
Measurement Data ◽  
Entropy Method ◽  
Displacement Sensor ◽  
Metric Entropy ◽  
Plastic Phase

Due to the unique properties of polymer composites, these materials are used in many industries, including shipbuilding (hulls of boats, yachts, motorboats, cutters, ship and cooling doors, pontoons and floats, torpedo tubes and missiles, protective shields, antenna masts, radar shields, and antennas, etc.). Modern measurement methods and tools allow to determine the properties of the composite material, already during its design. The article presents the use of the method of acoustic emission and Kolmogorov-Sinai (K-S) metric entropy to determine the mechanical properties of composites. The tested materials were polyester-glass laminate without additives and with a 10% content of polyester-glass waste. The changes taking place in the composite material during loading were visualized using a piezoelectric sensor used in the acoustic emission method. Thanks to the analysis of the RMS parameter (root mean square of the acoustic emission signal), it is possible to determine the range of stresses at which significant changes occur in the material in terms of its use as a construction material. In the K-S entropy method, an important measuring tool is the extensometer, namely the displacement sensor built into it. The results obtained during the static tensile test with the use of an extensometer allow them to be used to calculate the K-S metric entropy. Many materials, including composite materials, do not have a yield point. In principle, there are no methods for determining the transition of a material from elastic to plastic phase. The authors showed that, with the use of a modern testing machine and very high-quality instrumentation to record measurement data using the Kolmogorov-Sinai (K-S) metric entropy method and the acoustic emission (AE) method, it is possible to determine the material transition from elastic to plastic phase. Determining the yield strength of composite materials is extremely important information when designing a structure.

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