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Background. In patients with cerebral palsy (CP), secondary orthopedic deformities and violations of the walking pattern are often observed, so various methods of treatment are used for its correction, including orthosis. Abroad, orthoses (AFO) for ankle joints are most often used in clinical practice, whereas in Russia complex orthopedic shoes are used. At the same time, there are no comparative studies investigating the influence of these orthopedic products on the biomechanical parameters of gait. The aim of the study was to compare the kinematic parameters of walking in children with cerebral palsy, depending on the type of fixation of the foot and ankle joint. Methods. 25 biomechanical studies (9 barefoot tests; 7 tests in orthopedic shoes; 9 tests in AFO) were conducted in 9 patients with GMFCS 2 and GMFCS 3 levels of global motor function impairment. Results. The analysis showed that using AFO compared to walking barefoot, regardless of the GMFCS level, positively affects the space-time characteristics of walking, the kinematics of the ankle and knee joints, without significantly affecting the function of the hip joint. In this regard, an improvement in the integral indicator the gait index was noted. The use of orthopedic shoes in patients with GMFCS 2 and GMFCS 3 levels of global motor functions led to an improvement in the kinematics of the ankle and knee joints. At the same time, in patients in the GMFCS 2 group, the use of orthopedic shoes provided an improvement in more components of the gait index, whereas in the GMFCS 3 group, the number of such variables was significantly less. A comparative analysis of the results showed that the kinematic parameters of walking in orthopedic shoes are better in patients of the GMFCS 2 group, but in the GMFCS 3 group it is significantly better when using AFO. Conclusion. The choice of the type of foot fixation in patients with cerebral palsy, taking into account the level of global motor functions impairment, can significantly affect the correction of biomechanical parameters of walking.

In the article, a physical and mathematical model of the convective movement of air layers between the panes of a double-glazed window has been developed. The conducted studies and analysis of thermohydrodynamic processes in a window pane made it possible to obtain dependencies for choosing the optimal distance between panes and, if necessary, to make a choice between single-chamber or multi-chamber window panes for glazing agricultural buildings. Experimental studies of the temperature regime of window panes in natural conditions are presented, as well as using a special heat chamber. The obtained calculated dependencies can be used in the selection and design of the design of energy-efficient light openings for both agricultural production facilities and residential buildings.

Radiography of the spine makes it possible to assess disorders in the global sagittal balance of the spine only in statics. Therefore, the assessment of the dynamic sagittal balance according to the data of three-dimensional (3D) gait analysis including the balance of the trunk in general (in the sagittal and frontal planes) and the lumbosacral area, in particular, and determination of the compensatory mechanisms employed by the patient while walking due to the body segments and limbs, is getting more topical. Foreign publications on these topics in the last decade in the search resources of PubMed, e-Library, Cochrane Library and Scholar Google are not numerous, and there are no domestic ones at all, that, in turn, requires an independent detailed study. Purpose Primary analysis of the literature with the identification of methods and criteria for assessing the dynamic balance of the body. Materials and Methods In preparation of the review, the search and information resources of PubMed, eLibrary, Cochrane Library and Scholar Google were used. In the resources of the scientific e-Llibrary, there are no publications on the sagittal dynamic balance, that, in turn, requires an independent detailed analysis. Results and Discussion The postural model that considers the trajectory of movement of the center of mass (CoP) below foot was used to assess the dynamic sagittal balance. It is possible to evaluate the compensatory mechanisms for maintenance of dynamic sagittal balance basing only on the data of three-dimensional (3D) analysis of gait motions. Compensated / decompensated condition of the dynamic balance was defined according to the data of the ground reaction in 3 planes, the motions of the chest with regards to the pelvis, and according to the evaluation of the frontal vertical alignment (CVA-G) and sagittal vertical alignment (SVA-G). Conclusion The standard medical block for 3D gait analysis allows to perform quantitative estimation of compensatory mechanisms for sagittal imbalance, such as in-phase / antiphase coordination pattern of the trunk with regards to the pelvis; the compensated / decompensated condition of the dynamic balance according to the Ground Reaction data in three planes; and compensatory mechanisms, manifested in the parameters of the kinetics and kinematics of the lower limb joints. Assessment of dynamic sagittal balance is carried out in laboratories, where there is a software with an additional calculation option. Two main directions were proposed for its formation, taking into account either the maximum approximation to the X-ray criterion, or to the anatomical position of the center of mass.

BACKGROUND: In children with spastic forms of cerebral palsy often prescribed difference type of trunk-hip-knee-ankle foot orthosis (THKAFO). At the same time, we have not found any significant reports in the world literature dedicated to the study of the influence of these orthosis on the gait biomechanical parameters. AIM: To demonstrate the results of a comparative analysis of the effect of trunk-hip-knee-ankle-foot orthosis and ankle-foot orthosis on the gait biomechanical parameters in children with cerebral palsy. MATERIALS AND METHODS: The study involved two 13-and 15-year-old children with a diagnosis of cerebral palsy, spastic diplegia, GMFCS 3, MACS 23, Ashworth Scale 23. Six studies were conducted ― three tests for each child (barefoot, in AFO and THKAFO) using the 3D video analysis system Qualisys (Sweden). The spatio-temporal and kinematic indicators of gait, as well as the gait index, were evaluated. RESULTS: Analysis of the results in patient D. demonstrated that using the THKAFO in comparison with AFO led to a slight improvement in spatio-temporal gait indicators (from 4.012.5%), but to a deterioration in hip kinematics and a deterioration in the gait index (2.528.1%). Whereas in patient A., it was noted that the use of the THKAFO in comparison with AFO had a negative effect on the spatio-temporal parameters of gait (4.097.6%), on the kinematics of the knee and ankle joints, and on the improvement of the hip kinematics in the sagittal plane, but the effect on the gait index was not unambiguous. According to the totality of the analyzed data, patient D. was recommended to wear AFO instead of the THKAFO. Patient A. was also recommended to wear an AFO instead of a THKAFO, even despite the ambiguous results of the biomechanical research, since the final decision on the choice of the orthosis design took into account not only accurate changes in biomechanical parameters, but also a number of other factors, in particular social and household ones. CONCLUSION: In patients with level GMFCS 3, for improve the biomechanical parameters of gait, it is advisable to give preference to shorter and functional orthoses before prescribing orthoses that capture two or more body segments.

The global development of bioeconomy is impossible without technologies for comprehensive processing of plant renewable resources. The use of proven pretreatment technologies raises the possibility of industrial implementation of enzymatic conversion of polysaccharides from lignocellulose considering the process complexity. For instance, a well-tuned kraft pulping produces a substrate easily degraded by cellulases and hemicelulases. Enzymatic hydrolysis of bleached hardwood kraft pulp was carried out using an enzyme complex of endoglucanases, cellobiohydrolases, b-glucosidases and xylanases produced by recombinant strains of Penicillium verruculosum at a 10 FPU/g mixture rate and a 10 % substrate concentration. As a result of biocatalysis the following products are obtained: sugar solution, mainly glucose, xylobiose, xylose, as well as other minor reducing sugars; modified complex based on cellulose and xylan. The composition of biomodified kraft pulp was determined involving the use of HPLC. The method for determining the degree of crystallinity on an X-ray diffractometer was used to characterize the properties. The article shows the possibility of producing modified cellulose cryogels by amorphization with concentrated 85 % H3PO4 followed by precipitation with water and supercritical drying. Analysis of the enzymatic hydrolysate composition reveals the predominance of glucose (55...67 %) in reducing sugars with a maximum content of up to 6 % in the solution after 72 hours. The properties and structure of modified kraft pulp were shown to change during biocatalysis, in particular, the degree of crystallinity increased by 5 % after 3 hours of enzymatic hydrolysis. We obtained cryogels based on the initial and biomodified kraft pulp with conversion rates of 35, 50 and 70 %. The properties of these cryogels are not inferior to those based on industrial microcrystalline cellulose, as confirmed by the specific surface area, degree of swelling, porosity and SEM images. Thus, kraft pulp enzymatic hydrolysis offers prospects not only for producing sugar-rich hydrolysates for microbiological synthesis, but also for producing cellulose powders and cryogels with specified properties.

The solution of the problem of heat flux from a fin surface washed by gaseous media with different temperatures at asymmetric temperatures of the solid rib bases and unequal values of the heat transfer coefficients is obtained. The solution of the problem of heat transfer through a flat rib of constant cross section at different temperatures of the end sources, unequal media temperatures and different heat transfer coefficients on the surfaces of the rib is presented. The calculated dependencies can be used for designing heat-exchange devices in power plants, agricultural technological equipment systems, air conditioning, ventilation and heat supply systems.

The global development of the bioeconomy is impossible without technologies for comprehensive processing of plant renewable resources. The use of proven pretreatment technologies raises the possibility of the industrial implementation of the enzymatic conversion of polysaccharides from lignocellulose considering the process’s complexity. For instance, a well-tuned kraft pulping produces a substrate easily degraded by cellulases and hemicelulases. Enzymatic hydrolysis of bleached hardwood kraft pulp was carried out using an enzyme complex of endoglucanases, cellobiohydrolases, β-glucosidases, and xylanases produced by recombinant strains of Penicillium verruculosum at a 10 FPU/g mixture rate and a 10% substrate concentration. As a result of biocatalysis, the following products were obtained: sugar solution, mainly glucose, xylobiose, xylose, as well as other minor reducing sugars; a modified complex based on cellulose and xylan. The composition of the biomodified kraft pulp was determined by HPLC. The method for determining the crystallinity on an X-ray diffractometer was used to characterize the properties. The article shows the possibility of producing biomodified cellulose cryogels by amorphization with concentrated 85% H3PO4 followed by precipitation with water and supercritical drying. The analysis of the enzymatic hydrolysate composition revealed the predominance of glucose (55–67%) among the reducing sugars with a maximum content in the solution up to 6% after 72 h. The properties and structure of the modified kraft pulp were shown to change during biocatalysis; in particular, the crystallinity increased by 5% after 3 h of enzymatic hydrolysis. We obtained cryogels based on the initial and biomodified kraft pulp with conversion rates of 35, 50, and 70%. The properties of these cryogels are not inferior to those of cryogels based on industrial microcrystalline cellulose, as confirmed by the specific surface area, degree of swelling, porosity, and SEM images. Thus, kraft pulp enzymatic hydrolysis offers prospects not only for producing sugar-rich hydrolysates for microbiological synthesis, but also cellulose powders and cryogels with specified properties.

The re-entry vehicle included into the manned spacecraft Federatsiya that is being developed by RSC Energia, nominally lands on specially prepared solid ground landing sites using a parachute-jet system. In off-nominal situations the re-entry vehicle is capable of performing a splashdown. In that case, in order to properly take into account the loads and do strength analysis, one needs to know the levels of hydrodynamic loads on the spacecraft body and its dynamic behavior in water, factoring in all the possible weather conditions at the landing site and all possible operational modes of parachute-jet system in off-nominal situations. This paper presents the results of numerical simulation of a splashdown on rough water of the re-entry vehicle included in the crew transportation spacecraft Federatsiya. It discusses both the cases where the propulsion system is firing and where it is not. It provides data on changes in kinematic properties of the re-entry vehicle, in forces and torques it is subjected to, as well as g-loads it experiences. The obtained data are required for further loading and strength analyses of the spacecraft structure. Key words: numerical simulation, splashdown, re-entry vehicle, aerodynamic properties, rough seas

A methodological approach has been developed for the computational investigation of the thermal-hydraulic processes taking place in a sodium cooled fast neutron reactor based on a Russian computational fluid dynamics code, FlowVision. The approach takes into account the integral layout of the reactor primary circuit equipment and the peculiarities of heat exchange in the liquid metal coolant, and makes it possible to model, using well-defined simplifications, the heat and mass exchange in the process of the coolant flowing through the reactor core, and the reactor heat-exchange equipment. Specifically, the methodological approach can be used for justification of safety during the reactor cooldown, as well as for other computational studies which require simulation of the integral reactor core and heat-exchange equipment. The paper presents a brief overview of the methodological approaches developed earlier to study the liquid metal cooled reactor cooldown processes. General principles of these approaches, as well as their advantages and drawbacks have been identified. A three-dimensional computational model of an advanced reactor has been developed, including one heat-exchange loop (a fourth part of the reactor). It has been demonstrated that the FlowVision gap model can be applied to model the space between the reactor core fuel assemblies (interwrapper space), and a porous skeleton model can be used to model the reactor’s heat-exchange equipment. It has been shown that the developed methodological approach is applicable to solving problems of the coolant flow in different operating modes of liquid metal cooled reactor facilities.

This work presents the model of heat wall functions FlowVision (WFFV), which allows simulation of nonisothermal flows of fluid and gas near solid surfaces on relatively coarse grids with use of turbulence models. The work follows the research on the development of wall functions applicable in wide range of the values of quantity y+. Model WFFV assumes smooth profiles of the tangential component of velocity, turbulent viscosity, temperature, and turbulent heat conductivity near a solid surface. Possibility of using a simple algebraic model for calculation of variable turbulent Prandtl number is investigated in this study (the turbulent Prandtl number enters model WFFV as parameter). The results are satisfactory. The details of implementation of model WFFV in the FlowVision software are explained. In particular, the boundary condition for the energy equation used in high-Reynolds number calculations of non-isothermal flows is considered. The boundary condition is deduced for the energy equation written via thermodynamic enthalpy and via full enthalpy. The capability of the model is demonstrated on two test problems: flow of incompressible fluid past a plate and supersonic flow of gas past a plate (M = 3). Analysis of literature shows that there exists essential ambiguity in experimental data and, as a consequence, in empirical correlations for the Stanton number (that being a dimensionless heat flux). The calculations suggest that the default values of the model parameters, automatically specified in the program, allow calculations of heat fluxes at extended solid surfaces with engineering accuracy. At the same time, it is obvious that one cannot invent universal wall functions. For this reason, the controls of model WFFV are made accessible from the FlowVision interface. When it is necessary, a user can tune the model for simulation of the required type of flow. The proposed model of wall functions is compatible with all the turbulence models implemented in the FlowVision software: the algebraic model of Smagorinsky, the Spalart-Allmaras model, the SST $k-\omega$ model, the standard $k-\varepsilon$ model, the $k-\varepsilon$ model of Abe, Kondoh, Nagano, the quadratic $k-\varepsilon$ model, and $k-\varepsilon$ model FlowVision.

Background. The effect of different footwear profiles on knee adduction moment have not been fully studied. Methods. Fifteen healthy volunteer subjects, age 25.3 (±2.73), undertook a series of gait laboratory trials with adapted shoes. Kinematic and kinetic data were collect using 16 Oqus 3+ cameras and the walking speed was controlled using timing gates. High street shoes were adapted to include five different heel heights (varying from a 1.5 cm to 5.5 cm heels), two heel profile conditions (curved and semi-curved heels), three varying apex angles (10, 15, and 20 degrees), and barefoot and 3CR footwear conditions. The baseline shoe had no heel curve, a heel height of 3.5cm, an apex position of 62.5% of the shoe length, an apex angle of 15 deg, and a rigid forepart of the shoe. Results. The shoe with 5.5 cm heel height significantly increased the mean knee adduction moment during 50%–100% of the stance phase compared to the 1.5 cm heel (p = 0.008). The high heel shoe also significantly increased knee adduction impulse (area under the curve) versus the 1.5, 2.5, and 3.5 cm heels, and the 10° toe angle and barefoot condition. Ten degrees of toe angle reduced mean knee adduction moment during 0%–50% of the stance phase versus 20° and significantly reduced mean knee adduction moment during the late stance phase versus 15° and 20° toe angle footwear conditions. Walking with the curved heel for the healthy subjects increased mean knee adduction moment during 0%–50% of the stance phase compared to the heel without curvature (p < 0.0009). Conclusion. Further study is required to investigate those changes in patients with high risk of knee osteoarthritis.

Numerical investigation of mixing non-isothermal streams of sodium coolant in a T-branch is carried out in the FlowVision CFD software. This study is aimed at argumentation of applicability of different approaches to prediction of oscillating behavior of the flow in the mixing zone and simulation of temperature pulsations. The following approaches are considered: URANS (Unsteady Reynolds Averaged Navier Stokers), LES (Large Eddy Simulation) and quasi-DNS (Direct Numerical Simulation). One of the main tasks of the work is detection of the advantages and drawbacks of the aforementioned approaches. Numerical investigation of temperature pulsations, arising in the liquid and T-branch walls from the mixing of non-isothermal streams of sodium coolant was carried out within a mathematical model assuming that the flow is turbulent, the fluid density does not depend on pressure, and that heat exchange proceeds between the coolant and T-branch walls. Model LMS designed for modeling turbulent heat transfer was used in the calculations within URANS approach. The model allows calculation of the Prandtl number distribution over the computational domain. Preliminary study was dedicated to estimation of the influence of computational grid on the development of oscillating flow and character of temperature pulsation within the aforementioned approaches. The study resulted in formulation of criteria for grid generation for each approach. Then, calculations of three flow regimes have been carried out. The regimes differ by the ratios of the sodium mass flow rates and temperatures at the T-branch inlets. Each regime was calculated with use of the URANS, LES and quasi-DNS approaches. At the final stage of the work analytical comparison of numerical and experimental data was performed. Advantages and drawbacks of each approach to simulation of mixing non-isothermal streams of sodium coolant in the T-branch are revealed and formulated. It is shown that the URANS approach predicts the mean temperature distribution with a reasonable accuracy. It requires essentially less computational and time resources compared to the LES and DNS approaches. The drawback of this approach is that it does not reproduce pulsations of velocity, pressure and temperature. The LES and DNS approaches also predict the mean temperature with a reasonable accuracy. They provide oscillating solutions. The obtained amplitudes of the temperature pulsations exceed the experimental ones. The spectral power densities in the check points inside the sodium flow agree well with the experimental data. However, the expenses of the computational and time resources essentially exceed those for the URANS approach in the performed numerical experiments: 350 times for LES and 1500 times for ·DNS.

The article provides a development of recently published turbulence model KEFV. The submitted version of this model allows modeling transition in a separated flow. The model includes an adjustable mechanism for specifying generation of turbulence in laminar zones with high velocity gradients. The model is implemented in the FlowVision CFD software. Simulation of the air flow around low-Reynolds airfoil Eppler-387 is discussed in the article. The flow conditions are characterized by the Reynolds number Re = 200 000.

The structure and phase composition of dispersion-strengthened composite materials based on multicomponent aluminium alloys of the Al–Cu–Mg and Al–Si–Cu–Fe systems at various stages of mechanical alloying were studied by the methods of optical, scanning electron and ion microscopies, electron probe microanalysis and X-ray diffraction analysis. A possibility of the efficient use of commercial scrap of Al alloy chips and initially large strengthening ceramic particles as the base of composite materials was shown, as well as a possibility of synthesis of strengthening particles during the treatment. After mechanical alloying, these materials possessed a homogeneous and disperse structure, high hardness at room and elevated temperatures and a low linear thermal expansion coefficient.

This chapter examines the phase composition of alloys that contain zinc and magnesium as obligatory components. Many of these alloys also contain copper; therefore, the aluminum-magnesium-zinc (Al-Mg-Zn) and aluminum-copper-magnesium-zinc (Al-Cu-Mg-Zn) phase diagrams are basic for this group of alloys, which includes mainly wrought alloys of the 7XXX-series. Iron is a major impurity in alloys of 7XXX-series. The assessment of its influence on the phase composition and solidification reactions requires an analysis of the respective phase diagrams. The general appearance of the Al-Mg-Zn phase diagram, and also the liquidus, solidus, and solvus isotherms are provided. The chapter presents the invariant reactions involving (Al) and the respective monovariant reactions. The Al-Cu-Zn phase diagram is required for understanding the processes occurring in the quaternary Al-Cu-Mg-Zn system. Al-Cu-Mg-Zn phase diagram is the basis of the strongest aluminum alloys. Under real conditions, the solidification in 7XXX-series alloys completes with the formation of non-equilibrium eutectics at a temperature as low as 465-469°C.

This chapter discusses the phase composition of alloys with copper and manganese as the main components. Many casting and wrought alloys of the 2XX.0- and 2XXX-series belong to this system. As these alloys often contain magnesium, silicon, and iron as alloying elements or impurities, in most cases, the analysis of at least quaternary diagrams is required. The chapter describes the aluminum-copper-magnesium-manganese (Al-Cu-Mg-Mn) diagram that is essential for the correct analysis of the phase composition of important commercial alloys of the 2024-type. In these alloys, manganese has a significant effect on the phase composition, which makes insufficient the use of the ternary Al-Cu-Mg phase diagram only. The chapter describes Al-Cu-Mn phase diagram, which analyzes the phase composition of 224.0-type casting alloys and 2219-type wrought alloys at low concentrations of magnesium, iron, and silicon impurities in them. The invariant reactions occurring in Al-rich ternary alloys are listed. The chapter also describes Al-Cu-Fe-Mn phase diagram, which can be used in analyzing the effect of iron impurity on the phase composition of 2219-type alloys at a low concentration of silicon.

This chapter considers alloys that, apart from iron (Fe), silicon (Si), and manganese (Mn), contain no other elements capable of significantly affecting the phase composition.. These alloys are represented by commercial aluminum (1XXX-series) and some alloys of 8XXX- and 3XXX-series. The Al-Fe-Si system is the basic system for the structure analysis of commercial aluminum alloys of the 8111 type and binary Al-Si alloys, which, as a rule, contain an iron impurity. The Al-Fe-Mn-Si phase diagram can be used to analyze the effects of Fe and Mn on the phase composition of casting Al-Si alloys of the 4XX.0-series. The phase diagrams of Al-Fe-Si, Al-Fe-Mn, Al-Mn-Si, and Al-Fe-Mn-Si systems are illustrated in the chapter. The chapter deals with the commercial aluminum and 8111-type alloys.

This chapter deals with the phase composition of alloys containing nickel. It chapter discusses aluminum-iron-nickel (Al-Fe-Ni) phase diagram for the analysis of the phase composition of an 8001 alloy that contains only nickel and iron as the alloying elements. In the Al-Fe-Ni ternary system, the Al 3 Fe, Al 3 Ni, and AI 9 FeNi phases are in equilibrium with the aluminum solid solution. The Al 3 Fe phase dissolves up to 3-4% Ni, and no more than 1% Fe can be dissolved in the Al 3 Ni phase. Further, Al-Ni-Si phase diagram system is described to analyze multi-component alloys involving nickel and silicon, particularly piston alloys of the 3XX.0 series. Aluminum-copper-nickel (Al-Cu-Ni) phase diagram analyzes the 2618-type heat-resistant alloys and 339.0-type piston alloys that contain nickel, copper, and other alloying components.

This chapter discusses the phase composition of metal-matrix composite materials (MCMs) based on the aluminum-carbon-silicon (Al-C-Si) and aluminum-oxygen-silicon (Al-O-Si) systems. These MCMs have a matrix of aluminum or its alloys reinforced with fibers or particles of silicon dioxide (SiO 2 ), aluminum oxide (Al 2 O 3 ), or silicon carbide (SiC). The Al-C-Si system is the basis for aluminum-matrix composites reinforced with SiC. The Al-O-Si phase examines the interactions between aluminum on one side and Al 2 O 3 , SiO 2 , and mullite (AlSiO) on the other. From the analysis of the Al-O binary system, it follows that in the absence of water a stable compound, Al 2 O 3 (47.1% O) is in equilibrium with aluminum solid solution. The chapter considers the interaction between aluminum matrix and SiC reinforcement and suggests some metastable and non-equilibrium section of the Al-C-Si phase diagram as applicable to the composite materials. It discusses two types of MCMs for the examination of the interaction between the matrix and the reinforcing phases: MCMs containing 20% SiC particles and MCMs containing 10 vol.% SiC fibers.

This chapter deals with some phase diagrams of aluminum with transition metals, including scandium and rare-earth elements. It presents general features of stable and metastable interaction between aluminum and transition metals alongside some metastable phase diagrams. The main peculiar feature of transition metals in aluminum (Al)-based alloys is the formation of supersaturated solid solutions and, at some specific compositions, quasi-crystalline and amorphous materials during solidification. Some transition metals, such as nickel and iron, are used as major alloying additions to aluminum alloys in order to improve elevated temperature properties. The chapter examines equilibrium and non-equilibrium phase diagrams of some Al-based systems relevant to commercial and emerging alloys produced by conventional or rapid solidification routes. First, phase diagrams of alloys containing titanium, scandium, and zirconium are discussed. These systems are important for grain refining and recrystallization control. Then, alloying systems for conventional, rapidly solidified, and amorphous materials are considered.

This chapter begins with the description of ternary aluminum-magnesium-manganese (Al-Mg-Mn) phase diagram, which analyzes the base phase composition of 5XXX- and 5XX.0-series alloys. It reveals that commercial alloys of Al-Mg-Mn system constitute the 5XXX-series of wrought alloys and 5XX.0-series of casting alloys. These alloys are characterized by high corrosion resistance, good technological plasticity and surface quality, excellent weldability, and moderate strength. The properties of 5XXX-series alloys are achieved during casting, deformation, and annealing and are due to solid-solution hardening, work hardening, and controlled recrystallization. Commercial wrought alloys of the 5XXX series contain 1 to 7% Magnesium (Mg), 0.1 to 1% Mn, less than 0.25% Copper (Cu), 0.25% Zinc (Zn), and small additions of titanium (Ti), chromium (Cr), vanadium (V), and berellium (Be). Casting alloys of the 5XX.0-series may contain up to 12% Mg, up to 0.75% Mn and additions of Ti, zirconium (Zr), Cr, V, and Be. Impurities of iron and silicon greatly contribute to the phase composition and properties of commercial alloys. After that, the phase composition of commercial wrought and casting alloys is discussed, including some representatives of 3XXX- and 3XX.0-series alloys, the analysis of which can be performed using the Al-Fe-Mg-Mn-Si phase diagram.

Publisher Summary This chapter focuses on equilibrium phase diagrams of aluminum-copper-lithium (Al-Cu-Li), aluminum-lithium-magnesium (Al-Li-Mg), aluminum-lithium-manganese (Al-Li-Mn), aluminum-lithium-silicon (Al-Li-Si), aluminum-lithium-zirconium (Al-Li-Zr), and aluminum-copper-lithium-magnesium (Al-Cu-Li-Mg). Two binary and three ternary phases are in equilibrium with the aluminum solid solution in the aluminum corner of the Al-Cu-Li system. The structure parameters, composition, and density of these phases are listed. The solidification reactions in Al-rich alloys are shown and invariant reactions are also listed. Some of the Al-Cu-Li alloys contain small amounts of magnesium. The chapter discusses the implications of this addition on the phase composition and solidification. The Al-Li-Mg phase diagram analyzes commercial Al-Li alloys containing magnesium, such as Russian Grade 1420. The isothermal sections of Al-Li-Mg system at two temperatures are demonstrated. Limit solubilities of Mg and Li in solid aluminum at different temperatures are provided. The Al-Li-Mn phase diagram is studied in the range of Al-rich alloys. The Al-Li-Si system is considered as a base for rapidly solidified alloys and composite materials with Al-Li matrix and silicon carbide (SiC) reinforcement. The chapter describes the application of phase diagrams to commercial Al-Li alloys including effects of some additions, and the phase composition and structure of Al-Li alloys after precipitation hardening.

Publisher Summary This chapter begins with the description of ternary aluminum-magnesium-manganese (Al-Mg-Mn) phase diagram, which analyzes the base phase composition of 5XXX- and 5XX.0-series alloys. It reveals that commercial alloys of Al-Mg-Mn system constitute the 5XXX-series of wrought alloys and 5XX.0-series of casting alloys. These alloys are characterized by high corrosion resistance, good technological plasticity and surface quality, excellent weldability, and moderate strength. The properties of 5XXX-series alloys are achieved during casting, deformation, and annealing and are due to solid-solution hardening, work hardening, and controlled recrystallization. Commercial wrought alloys of the 5XXX series contain 1 to 7% Magnesium (Mg), 0.1 to 1% Mn, less than 0.25% Copper (Cu), 0.25% Zinc (Zn), and small additions of titanium (Ti), chromium (Cr), vanadium (V), and berellium (Be). Casting alloys of the 5XX.0-series may contain up to 12% Mg, up to 0.75% Mn and additions of Ti, zirconium (Zr), Cr, V, and Be. Impurities of iron and silicon greatly contribute to the phase composition and properties of commercial alloys. After that, the phase composition of commercial wrought and casting alloys is discussed, including some representatives of 3XXX- and 3XX.0-series alloys, the analysis of which can be performed using the Al-Fe-Mg-Mn-Si phase diagram.

This chapter discusses the phase composition of alloys containing silicon and copper as main components. It deals with the alloys belonging to the aluminum-copper-iron-magnesium-silicon (Al-Cu-Fe-Mg-Si) system, and describes the five-component phase diagram. The equilibrium and non-equilibrium phase composition of wrought alloys of the 2XXX-series and of the 6XXX-series alloys containing copper can be properly analyzed only using the Al-Cu-Mg-Si-(Fe) phase diagram. The chapter mentions that the Al-Cu-Si phase diagram can be used to correctly analyze the phase composition of casting alloys of 3XX.0- and 2XX.0-series with low concentrations of iron and magnesium impurities. No ternary compounds are formed in the aluminum corner of the Al-Cu-Si system. Al-Cu-Mg phase diagram analyzes complex systems involving copper and magnesium. Al-Cu-Fe phase diagram is also required for the analysis of more complex phase diagrams involving Cu and Fe. Analysis of this system makes it possible to follow the effect of iron impurity on the phase composition of Al-Cu commercial alloys, if the concentrations of the other elements, especially those that may form own phases with iron, are low. Al-Cu-Mg-Si phase diagram system analyzes Cu-containing alloys of the 3XX.0-series, and also for some wrought alloys of the 2XXX-series and the 6XXX-series.