Dynamic Precipitation Behavior Research Articles

Effect of deformation temperature on the dynamic recrystallization mechanism and dynamic precipitation behavior of Mg-Gd-Nd-Zr alloy

The deformation temperature is an important factor influencing the thermal deformation behavior of alloys. In this paper, thermal compression tests of Mg-Gd-Nd-Zr alloy were carried out at 350 ∼ 500 °C using the Gleeble-3800 thermal simulator, and the dynamic recrystallization (DRX) mechanism and microstructure evolution of the alloy were investigated by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The results show that the basal slip a and pyramidal slip a+c were consistently high activity at the test temperatures. As the temperature increased, the pyramidal slip a was gradually activated. At 350 °C, monolayer necklace-like dynamic recrystallized (DRXed) grains were formed around the initial grains via discontinuous dynamic recrystallization (DDRX). At 400 ∼ 450 °C, the monolayer DRXed grains expanded into the initial grain via continuous dynamic recrystallization (CDRX) to form multilayer necklace-like DRXed grains. However, at 500 °C, no necklace-like structure was formed around the initial grains. The initial grains were split into subgrains by low angle grain boundaries (LAGBs), which continuously absorbed dislocations and rotated for DRX. In addition, at 350 ∼ 400 °C, the alloy produced significant precipitation bands (mainly β phase). Above 450 °C, the dynamic precipitation was significantly attenuated. Precipitates greater than 200 nm could well impede dislocation movement and induce DRX nucleation. Nevertheless, the precipitates at the grain boundaries of the DRXed grains in turn pined the grain boundaries, refining the DRXed grains.

Evolution of microstructure, texture and formability of Al–Mg–Si alloys at different hot rolling finish temperatures

The impact of hot rolling finish temperature (HRFT) on the evolution of microstructure, texture, as well as formability—including deep drawability and bendability—of Al–Mg–Si alloy was studied in present work. The obtained results reveal that HRFT has a notable influence on the dynamic softening and dynamic precipitation behaviors during the hot rolling process of the investigated alloy. This leads to the volume fraction and number density of micro-sized Mg2Si particles increase as the increase of HRFT, those of nano-sized particles decrease, and the dislocation density decrease, in the hot-rolled sheets. These microstructural variations persist in the cold-rolled sheets, subsequently affecting the ultimate microstructure, texture, as well as formability of T4P sheets. The deep drawability improves as the HRFT rises, as indicated by the increase in normal anisotropy (r‾) and decrease in planar anisotropy (Δr). This is attributed to the weakening of texture intensity. The bendability, quantified by the minimum hemming factor (Rmin/t), deteriorates as the HRFT rises from 260 °C to 390 °C, attributed to the strengthening of P component along with the weakening of Cube component. Conversely, with the HRFT rises from 390 °C to 420 °C, the bendability improves dramatically due to the significant reduction in the average grain size. A combination of excellent deep drawability and bendability could be obtained by elevating the HRFT to 420 °C, attributed to the combined effect of weakened texture intensity and fine grains.

High strength and high ductility Mg-Gd-Y-Zn-Zr alloys obtained by controlling texture and dynamic precipitation through LPSO phase structure of different initial morphologies

High strength and high ductility Mg-Gd-Y-Zn-Zr alloys obtained by controlling texture and dynamic precipitation through LPSO phase structure of different initial morphologies

Dynamic Recrystallization Nucleation Mechanism and Precipitation Behavior of Homogeneous Al-Zn-Mg-Cu Alloy during Hot Deformation

The hot deformation behavior of Al-Zn-Mg-Cu alloy was investigated by flow stress curves in isothermal hot compression experiments with deformation temperatures of 350–450 °C and strain rates of 0.01 s−1 to 1 s−1, and the constitutive equation of homogeneous alloy was obtained. At the same time, the dynamic recrystallization and precipitation behavior during hot deformation and the relationship between them and the Z parameters were studied by using EBSD and TEM. DRV is the main mechanism of dynamic softening. With the decrease in Z parameter, the softening mechanism changes from dynamic recovery to discontinuous dynamic recrystallization or continuous dynamic recrystallization. At a higher Z parameter, the dislocation density and precipitated phase density are also higher because the high dislocation density provides heterogeneous nucleation sites of the precipitated phase. A large number of precipitates in the alloy also inhibit the nucleation and growth of dynamic recrystallization by hindering dislocation movement and grain boundary migration.

Study on the precipitation behavior of the hot deformed 2195 Al–Li alloy after online quenching and its relation to the age-hardening response

The fine-grained structures following deformation would be retained by using online quenching treatment which would achieve the purpose of simplifying formation process and reducing energy consumption. This study examined the effects of hot deformations on grain morphology, dynamic precipitation behavior and age-hardening response of the alloy after online quenching. And the dynamic precipitates re-solution behavior after online assisted heating were analyzed. The results indicated that the age-hardening response of the alloy was primarily controlled by the deformation temperature, and the appropriate deformation temperature range for online quenching was determined as 475–500 °C. Most of the deformed grains exhibited <110>Al//CD orientation. The increase in deformation temperature induced the transformation of the deformed grains from <110>Al//CD to <100>Al//CD orientation. A number of coarse second phases would be observed when the alloy was deformed below the optimal temperature range (e.g. 450 °C). For this case, it was suggested that the deformed alloy was heated by online assisted heating for a short time with the remaining heat after hot deformation, promoting most of the dynamic precipitates to be re-dissolved before online quenching. As a result, the deformation temperature window suitable for online quenching in 2195 Al–Li alloy could be broadened to 450–500 °C.

Dynamic precipitation and dynamic recrystallization behaviors of Mg-Gd-Nd-Zr magnesium alloy during thermal compression deformation

In this paper, the dynamic precipitation and dynamic recrystallization (DRX) behaviors of Mg-7Gd-2Nd-0.5Zr (wt.%) alloy during thermal compression were investigated by optical microscopy (OM), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The hot compression tests were performed at 350–500 °C with strain rates of 0.003–1 s−1 and a strain of 0.7. The results indicate that dynamic precipitation and DRX occur in the deformed region under appropriate conditions, and that dynamic precipitation precedes DRX. Elevated deformation temperature and strain rate facilitate DRX but weaken dynamic precipitation. The dynamic precipitates were β (Mg5Gd) phases and were mainly located at the grain boundaries in the deformed regions. DRX can be promoted when the size of the granular precipitates is larger than 200 nm. The second phase particles located at the grain boundaries of the recrystallized grains can pin the grain boundaries to refine the recrystallized grains. There are three mechanisms of recrystallization nucleation: grain boundary bowing nucleation, dislocation pile-up induced nucleation, and particle-stimulated nucleation (PSN). Moreover, a critical strain model and a kinetic model for the DRX of the alloy were developed.

Dynamic precipitation and deformation behaviors of a bimodal-grained WE43 alloy with enhanced mechanical properties

Achieving a high strength-ductility synergy in rolled Mg alloys remains a major challenge, especially for Mg alloys with high contents of rare earth (RE) elements, which are hard-to-deform and exhibit poor formability. In the present work, a bimodal grain structure consisting of fine grains (FGs) and coarse grains (CGs) has been achieved in a novel WE43 alloy sheet prepared by the hard-plate rolling (HPR) technique, which breaks the strength-ductility trade-off dilemma of the conventional WE43 alloy. Notably, the yield strength (YS) reaches as high as ∼312 MPa, presenting a remarkable improvement of YS (∼60 MPa) in comparison to conventionally rolled counterparts. Meanwhile, the ultimate tensile strength (UTS) and elongation-to-failure (EF) are ∼332 MPa and ∼11.8%, respectively, much higher than those of the wrought WE43 alloy reported in literature. Specifically, the disparate dislocation slips and dynamic precipitation behaviors in FGs and CGs have been studied in detail by combining EBSD and TEM analysis. The discrepancy of dynamic precipitation behavior in FGs and CGs is originated from the heterogeneous dislocation slip-dominated deformation behavior during HPR, related to initial grain orientations. It reveals that basal slips are dominant in the FG area, where equilibrium β-Mg14Nd2Y phase has precipitated along grain boundaries. In contrast, non-basal slips are prevalent and the metastable short rod-shaped β1 phase has formed within CGs. The enhanced YS of the present HPRed WE43 alloy sheet is mainly attributed to the formation of large amounts of extremely fine grains with an average size of ∼0.94 μm. The enhanced Orowan strengthening comes from the interaction between short rod-shaped β1 particles and non-basal dislocations (prismatic <a>, pyramidal <c + a> and pyramidal <a> dislocations) in CGs. In particular, the interactions between β1 particles and pyramidal <a> dislocations dominate the Orowan strengthening, leading to an increase of ∼34 MPa in the YS. Basal to basal slip transfers have been observed in FGs while non-basal slips are prevalent in CGs, which could be helpful for release the stress concentration near GBs. It is beneficial for preventing earlier fracture and thus enhancing the tensile strength combined with decent ductility.

Recrystallization Behavior of a Mg-5Zn Alloy Influenced by Minor SiCp during Hot Compression

The influence of minor SiCp on the dynamic recrystallization (DRX) and dynamic precipitation behaviors of the Mg-5Zn matrix were investigated through the hot compression test. The results showed that the addition of SiCp improved the DRXed ratio of Mg-5Zn matrix, but the recrystallized grains in 1 vol.% 5 μm SiCp/Mg-5Zn material were mainly formed by the "bulging" nucleation of the grain boundary at a low compressive strain (~0.05, ~0.1 and ~0.35), and PDZ (particle deformation zone) around SiCp had little effect on the recrystallization nucleation. However, the fine recrystallized grains appeared around the particles when the compressive strain reached ~0.7, which was attributed to the promotion effect of PDZ on recrystallization nucleation. This shows that PDZ around particles can promote DRX nucleation under large strain. Meanwhile, compared to the Mg-5Zn alloy, the volume fraction and size of the secondary phase in the SiCp/Mg-5Zn material increased due to the influence of SiCp on the recrystallization behavior of Mg-5Zn matrix.

Hot Processing Map and Dynamic Precipitation Behavior of 1460 Al–Li Alloy During Hot Deformation

Hot Processing Map and Dynamic Precipitation Behavior of 1460 Al–Li Alloy During Hot Deformation

Achieving advanced elevated-temperature strength by tailoring precipitates in Mg-Sn-Y alloys

The Mg-Sn-Y alloys exhibiting advanced elevated-temperature strength up to 300 ℃ were newly developed by tailoring precipitates through partially substituting and increasing yttrium (Y) (2, 3.5 wt%) for tin (Sn) in Mg-2.5Sn alloy. The effects of precipitates on the room/elevated-temperature mechanical properties, and the related dynamic precipitation behavior were investigated. The elevated-temperature strengthening mechanism of the alloy was revealed. The precipitates transformed from Mg2Sn in Mg-Sn alloy to Sn3Y5 in Mg-Sn-Y alloys. The abundant Sn3Y5 nanoparticles formed in the as-extruded Mg-0.5Sn-3.5Y alloy which exhibited significant higher peak strength as 223 MPa compared to that of Mg-2.5Sn as 53 MPa. The calculation of the critical nucleation energy for dynamic precipitation indicated that the Mg-Sn-Y alloys exhibited a smaller nucleation barrier for dynamic precipitation of dense nanoscale Sn3Y5 particles compared to the Mg-Sn alloy. This barrier was further decreased with increasing Y content, as exemplified by the increased area fraction of nanoparticles in the Mg-0.5Sn-3.5Y alloy. The abundant Sn3Y5 nanoparticles can inhibit the grain boundary crack propagation, and the formed fine grains (~3.8 µm) can effectively hinder the dislocation motion. Therefore, the present work demonstrated that coupling a high area fraction of thermally stable nanoparticles with grain refinement can provide an effective approach to acquire superior elevated-temperature strength for Mg alloys.

T1 precipitate bands and particle stimulated nucleation in 2195 Al-Cu-Li alloy during hot deformation

Dynamic precipitation and recrystallization behavior during middle-temperature and appropriate strain rates provide a chance to obtain desirable structure, which significantly improve the mechanical properties of aluminum alloys. In this paper, the microstructure evolution in the typical regions of processing map of 2195 Al-Cu-Li alloy during hot compression was observed via comparative characterization. The effects of dynamic precipitation and particle stimulated nucleation (PSN) on dynamic recrystallization have been analyzed systematically. At lower temperatures and higher strain rates, microshear band leads to a low power dissipation and provides preferential nucleation sites for T 1 precipitates. With temperature increases (<500 °C) and strain rate decreases, the T 1 precipitate bands are formed gradually due to the regular nucleation process on the microshear bands, which therefore limits the further growth of subgrains. Fine recrystallized grains along the grain boundary can also be obtained at high temperature via PSN stimulated by adequate stored energy, which was provided by large deformation near coarse secondary phases. Comprehensive continuous dynamic recrystallization (CDRX) is more prone to occur with the decrease of strain rate, leading to a higher power dissipation at 500 °C / 0.01 s −1 . • The relationship between microstructure evolution and hot processing map of 2195 Al-Cu-Li alloy have been investigated. • The formation of T 1 precipitate bands was described, and its influence on dynamic recrystallization has been discussed. • The dynamic recrystallization behaviour around grain boundaries has been discussed.

Effect of Sm on microstructures and mechanical properties of Mg–Gd(–Sm)–Zr alloys by hot extrusion and aging treatment

We investigated the effect of Sm on microstructures and mechanical properties of Mg–Gd (–Sm)–Zr by hot extrusion and aging treatment. The dynamic recrystallization (DRX) and precipitation behavior were analyzed by the electron backscattering diffraction (EBSD) and transmission electron microscope (TEM). For as-extruded alloys, the addition of Sm promotes DRX and dynamic precipitation, and the dynamic precipitation can activate the particle-stimulated nucleation (PSN) mechanism to promote the nucleation of DRX. The DRX grains of the as-extruded Mg–Gd–Zr show a random texture, but the as-extruded Mg–Gd–Sm–Zr shows an abnormal texture (<0001>Mg was parallel to the extrusion direction). For the extruded-aged alloys, the matrix precipitates of the Mg–Gd–Zr and Mg–Gd–Sm–Zr were all β′. But the size of β′ in Mg–Gd–Sm–Zr was smaller. The grain boundaries precipitates of the two alloys were all β. The β phase of Mg–Gd–Zr was granular and distributed discontinuously, while that of Mg–Gd–Sm–Zr was continuous distribution. Furthermore, there was an obvious precipitation-free zone of extruded-aged Mg–Gd–Sm–Zr. The high-temperature mechanical properties of extruded-aged Mg–Gd–Sm–Zr were obviously improved by the addition of Sm. The tensile strength, yield strength and elongation at 200 °C were 336 MPa, 271 MPa and 7.4%, respectively. Finally, the strengthening mechanism of extruded-aged Mg–Gd–Sm–Zr was analyzed in detail.

Dynamic Recrystallization Mechanism and Precipitation Behavior of Mg-6Gd-3Y-3Sm-0.5Zr Alloy During Hot Compression

Dynamic Recrystallization Mechanism and Precipitation Behavior of Mg-6Gd-3Y-3Sm-0.5Zr Alloy During Hot Compression

Dynamic and Static Precipitation Behaviors and Resultant Mechanical Properties of Al–15Zn–0.5Mg–0.5Sc Alloy

Dynamic and Static Precipitation Behaviors and Resultant Mechanical Properties of Al–15Zn–0.5Mg–0.5Sc Alloy

Influence of heat treatment and pre-straining on dynamic precipitation and creep behavior of AZ91-0.5Y magnesium alloys

Herein, the effect of heat treatment and pre-straining on dynamic precipitation and creep properties of an extruded AZ91-0.5Y magnesium alloy is systematically investigated. Four kinds of samples processed by solid solution (SS), aged after solid solution (SA), pre-strained after solid solution (SP) and subsequently aged (SPA) were prepared. The creep tests were conducted at different temperatures, ranging from 150 to 180 °C, under various applied stresses, ranging from 50 to 70 MPa. The results reveal that the highest creep resistance is found in the SP sample, followed by SPA and SS samples, and the lowest creep resistance is exhibited by the SA sample. The microstructural results clarify that the creep resistance can be related to the type and density of dynamically precipitated Mg17Al12 phase. For the SS and SA samples, a high volume fraction of lamellar structures of Mg17Al12 is formed during creep test, making basal <a> slip and prismatic <a> slip as the dominant creep mechanisms. The twins introduced by the pre-straining contributed a high volume fraction of spherically-shaped Mg17Al12 phase, making pyramidal <c+a> slip and twinning as the dominant creep mechanisms for SP and SPA samples. The twinning and high volume fraction of spherically-shaped Mg17Al12 phase are the reasons for the optimal creep properties of the SP sample.

Improved Thermal Stability and Enhanced Thermoelectric Properties of p-Type BaCu2Te2 by Doping of Cl.

Doping in semiconductors is a widely implemented strategy for manipulation of carrier concentration, which is a critical parameter to regulate the thermoelectric performance. Stoichiometric BaCu2Te2 shows high hole concentration and unstable transport properties owing to the inherent Cu vacancy and dynamic precipitation behavior. In this work, Te has been partially substituted by Cl in BaCu2Te2 to suppress the overhigh hole concentration. Due to the high electronegativity of Cl, strong Cl-Cu bonds can significantly inhibit the Cu migration and the consequent dynamic precipitation. Meanwhile, nano-precipitate BaCl2 distributes in the grain boundary, acting as ionic blocking layers. Therefore, the thermal stability of the samples can be essentially improved via chemical bonding strengthening and grain boundary engineering. In terms of thermal transport, the introduced point defects and second phase strengthen the short-wavelength and medium-wavelength phonon scattering, leading to further reduced thermal conductivity. Eventually, the repeatable ZT value of BaCu2Te1.98Cl0.02 reached 1.22 at 823 K, which is higher by 19.6% compared with 1.02 of pristine BaCu2Te2. The average ZTs of BaCu2Te2-xClx (x = 0, 0.02, 0.04, and 0.06) in the temperature range of 323-823 K are 0.737 for x = 0.02, 0.689 for x = 0.04, and 0.667 for x = 0.06, which are 24.6, 17.2, and 13.4% higher than the average ZT of 0.588 corresponding to the undoped sample, respectively. The study shows that synergetic enhancements of thermal stability and thermoelectric properties can be achieved by strengthening chemical bonding and constructing ionic blocking layers in the grain boundary, which can be applied to other fast-ionic conductor thermoelectric materials.

Characterization of dynamic precipitation behaviors accompanying dynamic recrystallization in an Mg-Al-Zn-RE alloy

In the present study, we investigated the dynamic precipitation (DP) of Mg17Al12 phase accompanying dynamic recrystallization (DRX) during the deformation of an Mg-Al-Zn-RE alloy. Hot compressions at various strains, strain rates and temperatures were followed by microstructural characterization via scanning electron microscope (SEM) and energy-dispersive X-ray spectroscope (EDS). The precipitation during heating and holding was avoided by proper treatment to guarantee initial microstructures without Mg17Al12 phase. During hot compression, the DP of Mg17Al12 particles with blocky shape accompanies the DRX process and mainly occurs on the DRXed grain boundaries. The volume fraction, number density and average size of Mg17Al12 precipitates depend on both temperature and strain rate, while the influence of temperature is more prominent for volume fraction. Phenomenological models bridging the number density and average size of precipitates with deformation conditions (temperature and strain rate) were established and validated. The pinning effect of DP on the grain growth makes DRXed grain size deviate from the values predicted by the classical function of the Zener-Hollomon parameter. Influenced by the sensitiveness of the pinning effect, temperature makes more sense in trimming DRXed grain size than strain rate. Vickers hardness tests were also conducted after hot compression. The influence of DP on microhardness lies in its effect on grain refinement.

Dynamic recrystallization and precipitation behavior of a novel Sc, Zr alloyed Al-Zn-Mg-Cu alloy during hot deformation

The hot deformation behavior of a novel Sc, Zr alloyed Al-Zn-Mg-Cu alloy was explored in the isothermal hot compression test with a temperature range of 300–500 °C and a strain rate of 0.001–10 s −1 . The stress-strain curve, constitutive equation, and processing map were integrated to evaluate the flow behavior and hot workability of the studied alloy. Besides, the relationship between dynamic recrystallization and precipitation behavior and the Zener-Hollomon (Z) parameter during hot deformation was deeply explored. As lnZ decreased, the dislocation density decreased, while the misorientation angle increased. Meanwhile, with the decrease of lnZ, the amount of low-angle grain boundaries and medium-low-angle grain boundaries decreased. Moreover, dynamic recovery is the dominant dynamic softening mechanism, while three different dynamic recrystallization (DRX) mechanisms were the main DRX mechanisms at different lnZ values. Discontinuous DRX dominated at high lnZ value (lnZ ≥33.33); Continuous DRX (CDRX) dominated at middle lnZ value (23.4 < lnZ < 33.33); Geometric DRX dominated at low lnZ value (lnZ ≤23.44). Meanwhile, increasing lnZ value is conducive to precipitation behavior. The intragranular precipitates and grain boundary precipitates are identified as the phase containing Al, Fe, Mn, and Si, the equilibrium η phase containing Cu and Al 3 (Sc, Zr) particles. • The following constitutive equation of the experimental alloy is constructed: ɛ ̇ =1.110 × 10 13 [sinh (0.0160σ)] 5.170 exp(16981/RT). • The microstructure relied on the lnZ value during hot compression. • DDRX, CDRX, and GDRX were the dominant DRX processes at high, medium and low lnZ values respectively. • Increasing lnZ value is conducive to precipitation behavior.

Effects of interlayer temperature on the microstructures of wire arc additive manufactured Al-Zn-Mg-Cu alloy: Insights into texture responses and dynamic precipitation behaviors

Wire arc additive manufacturing (WAAM) has advantages in fabricating large-size high-strength aluminum due to unconcentrated heat sources and lower cooling rates. Successful practices in depositing high-strength 2000 series alloys have been reported extensively in recent years. However, research on the WAAM of ultra-high-strength 7000 series Al-Zn-Mg-Cu alloys is still in the feasibility verification stage. This study aims to clarify the complex relationship between microstructures and interlayer temperatures during WAAM in a high alloyed quaternary Al-Zn-Mg-Cu alloy. Single-pass multi-layered components were fabricated with interlayer temperatures of 100 ℃, 200 ℃, and 300 ℃ for microstructure characterization. A validated numerical model was used to simulate the thermal process and provide clues for mechanism analysis. Results show that higher interlayer temperatures lead to the non-uniform orientation of twin dendrites, refined grains, and increased high angle grain boundaries (HAGBs). But its effects on the phase type and chemical composition of second phases and precipitates are very limited. Rising interlayer temperatures help to accelerate the dynamic precipitation progress. In the thermal cycles of the specimens included in this work, the contribution of arc heat is vital to drive the dynamic precipitation process. In contrast, the contribution of interlayer temperature is very limited in general. However, higher interlayer temperatures do contribute more to driving the dynamic precipitation process. The non-uniform distribution of hardness was observed along the height direction of the fabricated specimens, where the evolution of hardness agrees well with the progress of dynamic precipitation. • Intricate microstructural responses to interlayer temperatures are clarified. • Multiscale microstructure characterization is combined with numerical simulation. • Dynamic precipitation mechanism and its influencing factors are discussed.

Dynamic precipitation and the resultant magnetostriction enhancement in [001]-oriented Fe-Ga alloys

Precipitation of dispersive nanoparticles has recently been found to yield superfunctional properties, such as the large and sensitive magnetostriction in body-centered-cubic (bcc) Fe-Ga alloys with face-centered-tetragonal (fct) nanoprecipitates, and applying this strategy to grain-aligned alloys may allow one to obtain better performance. However, the internal stress generated during directional solidification may alter the precipitation behaviors by accelerating atomic clustering, therefore, a careful analysis of the morphology of precipitates and solute partitioning is needed. Herein, we investigated the dynamic precipitation behavior in a directionally solidified Fe73Ga27 alloy with [001] orientation. Through comparisons with random polycrystalline sample subjected to the same aging treatment, we find that the [001]-oriented sample produces sparser fct nanoprecipitates and extra interfacial omega nanoprecipitates. The internal stress accelerates Ga partitioning between the fct nanoprecipitates and the matrix, hence reducing their nucleation sites. The internal stress also alters the mutual elastic interactions between matrix and precipitates, where the Bain strains of fct nanoprecipitates are mostly accommodated by forming Ga-enriched omega nanoprecipitates and {112}<111> stacking faults at the phase front, unlike that for random polycrystalline sample, where the Bain strains are accommodated by local tetragonal distortion of the matrix. As a result, the magnetostriction enhancement ratio is 40% for the grain-aligned sample, weaker than ~165 % for the random polycrystalline sample. Our results not only shed lights on the precipitation difference between stress-containing and stress-free aging conditions but also help to guide the microstructure design of superfunctional alloys in which the type, number density and size of nanoprecipitates should be carefully controlled.