Aluminum Solid Solution Research Articles

Tin Bronze Reinforced with Cu9Al4 Particles: Mechanochemical Synthesis and Consolidation by Sintering under Pressure

X-ray diffraction analysis and optical and electron microscopy have been used to study the effect of mechanical activation conditions of the Cu–12% Sn mixture with different Cu9Al4 modifier contents on the structure and phase composition and morphology of formed composites. The mechanochemical intro-duction of 10 wt % of the modifying additive into the matrix of mechanically synthesized tin bronze mainly results in the formation of a ternary Al0.05Cu0.9Sn0.05 solid solution of aluminum and tin in copper. In the case of the 20 wt % modifying additive, the final product contains a Cu0.9Sn0.1 tin solid solution in copper and Cu9Al4 intermetallics. Studies of the mechanical and tribological characteristics of the material prepared by sintering under a pressure showed that the intensity of wear of the material based on the Cu–12 wt % Sn mechanochemically synthesized bronze is insignificant lower than that of commercial bronze alloy CuSn10P; the coefficient of friction (f) decreases by ~1.3 times and the range of its values is sufficiently wide,f = 0.7–0.9. The modification of the Cu–12 wt % Sn mechanically synthesized bronze with the Cu9Al4 inter-metallics allowed us to decrease the intensity of wear by 1.3 to 1.6 times and to substantially decrease the coef-ficient of friction (by 1.2 to 1.6 times). The stable value f = 0.5 is reached for the mechanically activatedCu‒12 wt % Sn + 20 wt % Cu9Al4 composition. The introduction of the intermetallics results in the increase in the microhardness of the alloys by 1.6 to 2 times (to Hμ = 2730 MPa) compared to those of CuSn10P and mechanically synthesized bronzes.

Effect of annealing on the structure and phase composition of Cu-Al composite produced by conventional and accumulative HPT

The paper presents the first results of the investigation of the effect of annealing on the evolution of microstructure and phase composition of a Cu-Al composite obtained by accumulative high pressure torsion (HPT). Cu-Al composites produced under 6 GPa in 10 revolutions at room temperature with conventional and accumulative HPT were annealed at 450°C for 15 min. Electron microscopy and energy dispersive spectrometry analysis showed that annealing enhances the solid-state reaction. In the sample after conventional HPT and post-deformation annealing, grayer contrast layers containing intermetallic compounds were formed at the copper-aluminum interface. The contrast on the microstructure images of the sample after accumulative HPT and post-deformation annealing is more uniform than after conventional HPT and annealing. In the sample, a more intense phase transformation occurred. This led to a noticeable increase in the volume fraction of the intermetallic compounds up to 5 – 6 times. X-ray diffraction analysis indicates that in the annealed sample after accumulative HPT, alongside with initial copper, there is also a solid solution of aluminum in copper, which differs from copper with a crystal lattice parameter. Post-deformation annealing led to the formation of different quantity of intermetallic compounds in the studied samples.

Effect of HPT straining and further natural aging on the structure and hardness of aluminum alloy 1965 with nanosized TM aluminides

Pre-quenched samples cut from a homogenized ingot of commercial aluminum alloy 1965 with a grain size of about 21 µm were compressed at 6 GPa and then strained by torsion up to 10 revolutions at room temperature. TEM, SEM and XRD analyses showed that the strengthening / softening of the alloy during further natural aging up to 500 hrs was controlled by simultaneous decomposition of the aluminum solid solution and recovery of its deformation structure. It was found that the two-level nanostructuring of the alloy (precipitates and matrix) is accompanied by more than twofold strengthening up to a hardness of about 250 HV. The main contribution was made by dislocation and structural hardening due to the formation of a highly work-hardened structure of the nanofragmented type. During subsequent aging, the change in hardness was controlled by both the preliminary strain and the aging time. A continuous increase in strength with strain and aging time was found in the samples after pressing and torsion up to 1 revolution. In other conditions, strengthening was preceded by softening, the magnitude and duration of which were also proportional to the strain. The nature of the alloy behavior and the role of nanosized aluminides of transition metals are discussed in details.

Effect of the Processing Parameters of Doping Lime, Calcium and Zinc of Aluminium Alloys Recovered from Scrap

The present work shows the effect of the processing parameters of separately doping lime, calcium and zinc on the properties of an aluminium alloy recovered from scrap. Two routes viz pyrometallurgy and powder metallurgy were involved the parameters displayed by the concentration of the alloying agents, time and temperature have ‎been studied. Results showed that powder metallurgy promotes a wide spectrum for doping the host alloy. The doping process of lime to the molten aluminium needs more time as compared to the zinc metal. A heterogeneous structure of the eutectic phase developed with lime or calcium gradually affects the mechanical properties of the Al ‎alloy. It decreased the density by 15.5 %, and increases its hardness to about 37 V. Calcium formed a eutectic phase Al4Ca at lower concentrations. The eutectic (Al)+Al4Ca of fine ‎structure and the particles of Al4Ca are capable of spheroidization during heat treatment at ≥ 500 ‎°С. The maximum hardness observed with lime-containing Al alloy gives a reason to expect a slight ‎increase in mechanical strength properties. In the powder metallurgy method, Al was prepared by ‎chemical ‎victimization ‎reducer hydrazine hydrate. The Al-Ca-Zn system is promising for the development of new ‎eutectic type high-strength aluminium alloys. With zinc, the pyrometallurgy is far more convenient as compared to powder metallurgy. Zinc is uniformly distributed between ‎aluminium solid solution and the intermetallic phases of the Al-Zn-Ca system.‎ The ‎activation energy of adding lime or calcium to the Al alloy amounts ‎to 27.533, ‎kJ/mol with a recovery potency of 98.7%. A process of annealing regenerated homogeneous structure when matched ‎ under a flux of ‎carbon/alkali mix.

The influence of the Al2O3 particles on the microstructure of the mechanically alloyed Al-Mn-Cu alloy

The microstructure, phase composition and hardness evolutions of high-energy ball milled Al-15.3%Mn-6.2%Cu alloy and alloy matrix composites with 2% and 5% of Al2O3 fine particles were studied with scanning electron microscopy, X-ray diffraction, and differential thermal analysis. Milling provided for the dissolution of the Cu-bearing non-equilibrium CuAl2 and equilibrium Al20Cu2Mn3 phases of solidification origin. The minimum values of the aluminum solid solution lattice parameter of 0.4028 nm suggested 4.4 wt%Mn and 6.2 wt%Cu solute content in Al after milling for ∼5 h, this milling duration providing for the lowest microhardness. Solid solution decomposition with the precipitation of the Mn-enriched phase and precipitation hardening occurred with a further increase in milling time and during annealing of the pre-milled samples. The Al2O3 particles refined the mechanically alloyed granules, increased the microhardness and facilitated both the dissolution of the solidification origin phases and the precipitation of the Mn-enriched phase during mechanical alloying, and also improved the precipitation hardening effect.

Novel precipitation strengthened Al-Y-Sc-Er alloy with high mechanical properties, ductility and electrical conductivity produced by different thermomechanical treatments

This study investigated the evolution of the microstructure, mechanical properties, and electrical conductivity of novel Al-0.2Y-0.2Sc-0.3Er alloy in as-cast, as-rolled, and annealed states. Aluminum solid solution and τ2 (Al75–76Er11–17Y7–14) eutectic phase particles with a size of 50–200 nm were identified in the as-cast alloy sample by scanning electron microscopy investigation and phase diagram analyses. A precipitation strengthening mechanism was implemented during annealing at 300 °C for 7 h due to L12 precipitates of Al3(Sc,Y,Er) phase with a maximum diameter of 10 nm. The same structure was formed in the samples annealed at 300 °C for 7 h after rolling the as-cast alloy without aging treatment. The samples aged before rolling formed a more homogenous and finer substructure, with a grain structure formed after annealing rolled sheets. Significantly more uniform structures facilitate achieving higher strength and electrical conductivity. Al-0.2Y-0.2Sc-0.3Er alloy aged at 300 °C for 7 h, hot and cold rolled, and annealed at 300 °C for 7 h exhibited a good combination of strength and electrical conductivity: YS = 191 MPa, UTS = 207 MPa, El. = 14 %, and EC = 59.7 % IACS.

Управління структурою і властивостями ливарного алюмінієвого сплаву АМ4.5Кд (ВАЛ10) модифікуванням дрібнокристалічними лігатурами

To management the structure, mechanical and operational properties of the high-strength cast aluminum alloy АМ4.5Кд (ВАЛ10), the work uses a modification method based on the principle of structural inheritance, using rapidly cooled (Vcool. ≥ 10^5 °С/s) fine-crystal ligatures AlTi5 and AlZr10, and as well as ligatures of the chemical composition of the base alloy with nanoscale size of intermetallics and Alα crystals. Studies have shown that the introduction of fine-crystalline additives into the melt leads to a transition from a dendritic to a non-dendritic structure, a significant decrease in the size of the crystals of the Alα solid solution, and an increase in its degree of supersaturation. The microstructure becomes more uniform - the difference between the maximum and minimum size of the grains decreases. The most effective reduction of the grain size and the transition from dendritic to non-dendritic structure of the aluminum solid solution at increased cooling rates occurs when alloying with fine-crystal AlTi5 ligature introduced into the melt in terms of pure titanium 0.05-0.15 wt. %. We must think that the main factor of modification by rapidly cooled ligatures is the introduction of a large number of additional crystallization centers into the melt. After T6 heat treatment, the highest strength of AM4.5Kd alloy (VAL10) is achieved when modified with AlZr10 ligature, in particular, with a mass fraction of zirconium of 0.25%. Probably, this is mainly due to the expansion of the region of the solid solution of copper and zirconium in aluminum during high-speed cooling and its subsequent disintegration during heat treatment with the release of strengthening nano-sized CuAl2 and Al3Zr phases. Tribological studies of AM4.5Kd alloy (VAL10) were carried out. The alloy modified with fine crystal ligature of the base alloy composition in the amount of 12 wt.% has the highest wear resistance. Keywords: fine crystal ligatures, AM4.5Kd (VAL10), modification, microstructure, strength, wear resistance.

Mechanically stimulated reactions in metal–oxide (carbide) systems

The processes of mechanochemical reduction of oxides of iron, nickel, and copper with aluminum with a stoichio metric ratio of components and in mixtures with a two-, three-, and four-fold excess of the aluminum content over the stoichiometric, as well as in the presence of an excess of oxide-forming metal and solid solutions of aluminum in iron and copper, were studied by the Mössbauer and IR spectroscopy, X-ray diffraction analysis, including the use of synchrotron radiation, and electron microscopy. The conditions for formation of metals modified with aluminum oxide (iron, nickel, copper) and their monoaluminides are determined. High aluminum content aluminides are formed at a three-fold excess of aluminum, and at a four-fold excess, a mechanochemical reduction of oxides does not occur. The preferred method for modifying metals with alumina is the mechanochemical reduction of oxides with a solid solution of aluminum in the oxideforming metal. Mechanochemical interaction in the high-energy Hf–C system in the presence of 20, 30, and 50 wt. % copper leads to the formation of hafnium carbide; and with an increase in the copper content, the crystallite size decreases.

Influence of adjusting the anodizing and aging sequences on the microstructure, fatigue property and corrosion resistance of anodized AA6082 alloys

Compared with the traditional anodization of aged aluminum alloy, a novel process was carried out by anodic oxidation of solid solution aluminum alloy, followed by aging treatment to optimize the interface's composition and microstructure, under which the thickness, hardness and modulus of the oxidation film wouldn't be influenced and the strength of base materials kept the same. As β” precipitates cannot be formed in the subsequent aging process due to the consumption of Mg on the film-base interface, line defects caused by lattice distortion were avoided. Therefore, the stress concentration point in the fatigue process was reduced, and the fatigue property of the anodized material was improved from 89 MPa to 125 MPa. The anodizing of solid solution aluminum alloy helps the dispersion of Mg in the oxide film, which increases the self-corrosion potential of the oxide film from −0.97 V to −0.32 V and delays the occurrence of pitting corrosion during long-term immersion in 5 wt% NaCl solution.

Одержання виливків із доевтектичних силумінів способом тиксолиття

Experimental studies of the method of thixocasting of AK7ч hypoeutectic silumin using cylindrical billets with different initial prepared structure (dendritic and non-dendritic – rosette-like and globular) of the primary solid phase were carried out. It is shown that after casting using billets with the initial dendritic structure of aluminum solid solution, the structure in shaped castings remains dendritic. At the same time, a certain number of destroyed dendrites are observed in the structure, predominantly melted. The thixocasting of the hypoeutectic silumin AK7ч using billets with the initial rosette-like structure of primary aluminum crystals ensures the production of shaped castings with a globular structure of the primary phase with a globular size of 80–100 μm. At the same time resulting the globular structure of the primary solid phase in castings is homogeneous and evenly distributed over the entire cross section. Thixocasting of silumin AK7ч using billets with the initial globular structure of the primary solid phase does not lead to a change of the structure of the casting. This slightly increases the size of the globules in the casting. Eutectic colonies in shaped castings obtained by thixocasting are characterized by a higher degree of differentiation compared to the initial structures of billets. Determination of mechanical properties showed an increased plasticity of the investigated hypoeutectic silumin in castings obtained after thixocasting without additional hardening heat treatment. Keywords: thixocasting, hypoeutectic silumin, non-dendritic structure, globular structure, rosette-like structure, solid-liquid billet, shaped casting.

Effect of high-energy ball milling on the microstructure, phase composition and microhardness of the Al–Mn–Cu alloy

X-ray diffraction and scanning electron microscopy methods were used to study the effect of the planetary ball mill treatment time on the morphology, phase composition and microstructure of the Al–Mn–Cu-based alloy granules with and without nanodiamond particles. The phase composition of the alloy was determined by X-ray diffraction after casting and milling for 5–20 h. It was shown that nanodiamond particles promote granule coarsening, and this is especially noticeable with an increase in the milling time up to 20 h. At the same time, the size of initial alloy granules weakly depends on the processing time. Cu-bearing phases of crystallization origin dissolve during mechanical alloying. The lattice constant of the aluminum solid solution decreases after 5-hour treatment to 0.4028–0.4030 nm, and increases with further increasing milling time. Exothermic effects associated with the precipitation of secondary phases were revealed for mechanically alloyed granules during heating. An increase in the milling time reduces the intensity of peaks. The solidus temperature of samples decreased after mechanical alloying. For the nanodiamond-bearing sample, an exothermic effect is observed which can be ascribed to the aluminum carbide formation or oxidation reactions in nanodiamond particles. The maximum microhardness is achieved after 5–10 h of mechanical alloying, and the nanodiamond particles slightly increase the maximum microhardness from 316 to 330 HV. The results indicate the dissolution of copper and manganese in the aluminum solid solution after 5 h of treatment and their precipitation with the increasing milling time. Nanodiamond particles have no effect on the dissolution of elements but accelerate the solid solution decomposition with the increasing treatment time.

Structure and properties of AL–Cu–Yb alloy with iron and silicon impurities

The effect of iron and silicon impurities on the phase composition and properties of the Al–4.3Cu–2.2Yb quasi-binary alloy was determined. In addition to the aluminum solid solution and dispersed eutectic ((Al) + Al8Cu4Yb) containing about 1 % of dissolved iron, Al3 Yb/(Al,Cu)17Yb2 and Al80Yb5Cu6 Si8 phases were identified in the cast alloy microstructure (the latter was not found in an alloy of a similar composition but without impurities). After homogenization annealing at t = 590 °C for 3 h, the structure is represented by compact fragmented and coagulated intermetallic compounds 1–2 μm in size, and a solid solution (Al) with a maximum copper content of 2.1 %. The hardness of deformed sheets significantly decreases after 30 min of annealing, and then changes slightly in the following 5.5 h of annealing at t = 150÷210 °C. After annealing at 180 °C (τ = 3 h), a substructure with a subgrain size of 200–400 nm is formed in the alloy structure. Rolled sheet softening occurs due to recovery and polygonization processes after annealing at temperatures up to 250 °C, and due to recrystallization after annealing at temperature above 300 °C. After annealing at 300 °C (τ = 1 h), the recrystallized grain size is 7 μm. The grain increases to 16 μm after annealing at t = 550 °C (τ = 1 h). The alloy under study has a high level of mechanical properties (conditional yield limit is 205–273 MPa, tensile strength is 215–302 MPa, relative elongation is 2.3–5.6 %) in the annealed state after rolling. Iron and silicon impurities do not lead to the formation of coarse lamellar intermetallic phases and do not reduce the ductility of the investigated alloy.

Assessment of effects of aluminum solid solution decomposition on geometric structure of Al-Sn-Zn isobar phase diagram

Three-dimensional (3D) computer model of the Al-Sn-Zn isobaric phase diagram is presented. It is shown that the T-x-y diagram consists of 64 surfaces and 25 phase regions. Features of Al-Zn binary system phase diagram related to decomposition of aluminum solid solution and its influence on geometric structure of liquidus and solidus surfaces in the ternary system, formed by this binary system and tin, are considered. Critical analysis of the published data was carried out and errors in visualization of those fragments of the Al-Zn T-x diagram, in which phase regions are formed with the participation of new aluminum solid solutions, appeared after the decomposition of the initial solid solution, are discussed. To design this 3D model, literary data were used, and the assessment of its quality is based on isopleths and isothermal sections from the same primary sources.

Вплив швидкості охолодження на структуроутворення сплаву АМ4,5Кд (ВАЛ10)

High-strength cast aluminum alloy AM4.5Kd (VAL10) belongs to the Al-Cu system and due to the combination of a high level of physical, mechanical and operational properties, is widely used in high-tech industries and technology: aviation, space, shipbuilding, transport. Products from the alloy AM4.5Kd (VAL10) are obtained by all known methods of casting (in sand molds, in a chill mold, under pressure), differing in cooling rates. This has a significant effect on the structure and properties of the alloy, not only in the as-cast, but also in the heat-treated state, which determines the relevance of scientific work in this direction. The article presents the results of a study of the microstructure of the AM4.5Kd (VAL10) alloy with a change in its cooling rate during the curing process (Vcool.) from 0.4 °C/s to ≥ 105 °C/s. The alloy was melted, refined and, at a temperature of 750°C, poured into molds with different heat sinks. It is shown that an increase in the cooling rate during the hardening process leads to a decrease in the size of structural components, in particular, aluminum (Alα) solid solution crystals and to an increase in their microhardness. At a cooling rate of 0.4 °C/s, corresponding to solidification in a sandy form, primary Alα crystals are formed in the form of coarsened dendrites with an average size slightly larger than 800 μm, along the boundaries of which a fine network of particles of Al3Ti, Al12Mn2Cu phases and Alα+СuАl2 eutectics is formed. With an increase in the cooling rate, the branching of the dendrites and the volume fraction of the finely differentiated eutectic increase, the cooperative growth of phases in which is maintained throughout the entire range of cooling rates studied. The value of the dendritic parameter of the solid solution of aluminum regularly decreases with a practically unchanged shape factor of its crystals, which is almost up to Vcool. ≈ 105 °C/s is from 1.45 to 3.15. A similar dependence of the change in the macrograin size on the cooling rate was not found. Its anomalous growth was recorded at a cooling rate of ≥ 120 °C/s, at which the macrograin size is commensurate with the alloy cooled at a rate of 0.4 °C/s. In the work, such a discrepancy is explained from the standpoint of the theory of the nucleus and growth of crystals. Keywords: cooling rate, microstructure, AM4.5Kd (VAL10), structure formation, macrograin size.

Structural and morphological study of the Al–Si–Mg–SiC composite material produced by mechanical alloying

The research focuses on aluminum composite granules obtained by the mechanical alloying of VAS1 aluminum alloy and silicon carbide initial powders. It was found that the morphology and average size of composite granules change as the time of mechanical alloying increases. There are the processes of aluminum matrix plastic deformation and the introduction of silicon carbide particles into the matrix, «cold welding» of agglomerates to each other and the growth of an average granule size up to 550 μm that occur for 40 hours of processing. After longer mechanical alloying (60 h), the structure of composite granules becomes uniform, and the average particle size reaches ~150 μm remaining virtually unchanged as the process time increases. X-ray analysis showed that there is a change not only in the morphology of composite granules, but also in their internal structure: coherent scattering regions decrease, the lattice constant of the aluminum matrix alloy changes, microdeformations and stacking faults increase. Transmission electron microscopy studies were conducted in order to study the material microstructure more deeply. Their results proved that the material has a uniform ultra-fine grain structure. The solid solution of aluminum has a maximum grain size of 160 nm. Dislocation density in the composite is rather high. The structure features nanosized plate-like Si particles and silicon carbide existing in the material as distributed splintery coarse particles. No diffusion zone between SiC particles and the base material was found.

Effect of copper concentration and annealing temperature on the structure and mechanical properties of Al–2wt.%Mn ingots and cold rolled sheets

This study focuses on the development of new Al–Cu–Mn alloys with enhanced strength and heat resistance achieved without hightemperature exposure. Seven alloys were considered including ones containing permanent Mn content of 2 % and variable Cu content of 0– 4 %. It was found that ~ 2 % Mn is completely dissolved in the solid solution of aluminum, while copper in the cast structure is distributed between the solid solution of aluminum and Al 2 Cu eutectic phase inclusions. It was experimentally established that when the copper content is 2 and 3 %, the solid solution of aluminum contains approximately the same amount of copper – up to 1.5 %. The deformation plasticity of experimental alloys in the cold rolling mode with the reduction rate of 80 and 95 % was investigated. It was shown that no preliminary treatment is required for alloys containing up to 3 % Cu as they feature high rolling workability. Then, the effect of heat treatment in the annealing temperature range of 200–600 °C on the structural and phase parameters of the alloys was studied. Alloy hardening in the process of multistage annealing by means of hardness measurement was analyzed. The data obtained allowed us to determine the influence of copper and analyze the thermal stability of model alloys. Tensile tests of cold rolled sheets with a thickness of 0.5 mm with a reduction rate of 95 % of alloys containing 2 and 3 % copper showed high performance. Particularly, the alloy containing 3 % Cu has strength compatible with that of the 1201 alloy in the T6 state.

Accumulation of Defects in Polycrystalline Copper–Aluminum Solid Solutions and the Role of Stacking Fault Energy

Accumulation of Defects in Polycrystalline Copper–Aluminum Solid Solutions and the Role of Stacking Fault Energy

Effect of Melt Overheating on Structure and Mechanical Properties of Al-Mg-Si Cast Alloy

The paper discusses the complex effect of melt overheating with subsequent fast cooling down to the pouring temperature on the crystallization process, microstructure and mechanical properties of Al-Mg-Si aluminum alloy. The results obtained facilitated the establishment of rational modes of melt overheating, leading to a significant change in the dispersion and morphology of structural components. In particular, with an increase in the melt overheating temperature to 900 °C with holding and subsequent rapid cooling to the casting temperature, a decrease in the average size of dendritic cells of the aluminum solid solution from 39 μm to 13 μm was observed. We also noticed the refinement of eutectic inclusions of the Mg2Si phase with compact morphology. An increased level of mechanical properties was noted; the maximum values of tensile strength and elongation reached 228 MPa and 5.24%, respectively, which exceeded the initial values by 22.5% and 52.3%, correspondingly. The microhardness of the aluminum solid solution sequentially increased from 38.21 to 56.5 HV with an increase in the temperature during melt overheating. According to the EDS linear scanning, an increase in the superheat temperature of the melt is accompanied by an increase in the degree of saturation of the solid solution with magnesium.

Mechanical and tribological characteristics of AL7075/MWCNT, B4C & MoS2 hybrid metal matrix composites

Composites are profoundly thriving as replacement of ferrous alloys. The Aluminium is manifested into a greater substitute due to their properties like lightweight, low density, high strength, and good corrosion resistance. An endeavour has been made to synthesize Al7075 aluminium alloy with reinforcement of B4C and MoS2 under various weight percentages of 1.5%, 3%, 4.5% with MWCNT as a constant weight percentage of 0.2% using stir casting process. The cast samples were then extruded and their Mechanical and tribological properties were found. From the microscopical investigation, it has been observed that the reinforcement particles are uniformly distributed in the matrix alloy in aluminium solid solutions. The tensile strength and hardness of the reinforced composites is increased by the addition of reinforcements. Around 81% of the hardness and 4% of tensile strength is increased with the addition of the particulates. The coefficient of friction of the sample is reduced to a maximum of around to 63%. The significant improvement of wear resistance and coefficient of friction of aluminium hybrid composites has been achieved owing to inclusion of solid lubricant (MoS2) along with hard ceramic reinforcement particles (B4C) in the matrix alloy.

Quantitative analysis of the Portevin–Le Chatelier effect by combining digital image correlation and dead-weight-type tensile test

Abstract A quantitative evaluation method of a serration deformation behavior by a dead-weight tensile test combined with a strain measurement by a DIC method is proposed. This method applies to binary solid solution aluminum alloys and a ternary cluster strengthened aluminum alloy. In the dead-weight tensile test, the serrated flow was measured as a stress-strain curve with a stepped-shape divided into two stages of a stress rising phase and a strain burst phase. By adopting this tensile test, the serration deformation behavior can be measured with an extremely reproducibility. It was confirmed that an elastic deformation occurs predominantly in the stress rising phase, and this deformation behavior is discussed in relation to the concentration of solid solution elements. Propagation of PLC bands has occurred in the strain burst phase. An activation volume obtained from the strain rate in the PLC bands was in good agreement with a calculated value based on a distribution interval assuming a regular square distribution of solute elements. For the ternary alloy strengthened by clusters, it is also shown that this method can be applied to the qualitative estimation of the change in the residual amount of the solid solution element in the matrix during natural aging.