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Research Article  |  Open Access  |  4 Nov 2024

Machine learning driven design of high-performance Al alloys

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J Mater Inf 2024;4:19.
10.20517/jmi.2024.21 |  © The Author(s) 2024.
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Abstract

Aluminum (Al) alloys with both high strength and thermal conductivity (TC) are promising structural materials for wide application across different industries. Yet, design of such alloys is challenging, since strength and TC often share a trade-off. In this paper, we build prediction models for TC and ultimate tensile strength (UTS) of Al alloys using eXtreme gradient boosting (XGBoost) and support vector machine (SVM) algorithms, respectively. The models take physical descriptors from the alloy composition into account. Lasso and Gini Impurity algorithms were adopted for feature engineering. Guided by the models, an Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy with TC over 190 W·m-1·K-1 and UTS over 220 MPa was designed. The alloy was fabricated and tested by experiment, and its UTS and TC are close to the model prediction. Microstructure characterization suggests that the fragmented and spherical Si phase, along with a few non-spherical Si phases, may be a key reason for the improved properties.

Keywords

Aluminum alloys, strength, thermal conductivity, machine learning

INTRODUCTION

Aluminum (Al) alloys are widely used in automobile[1], aerospace[2] and marine[3] industries for their high specific strength, thermal conductivity (TC) and recyclability. In most Al alloys, an increase in strength is often accompanied by a decrease in TC. This occurs because the lattice distortion and secondary phases introduced by alloying not only contribute to solution and precipitation strengthening but also significantly scatter electrons and phonons, thereby reducing TC.

Due to the differences in valence state[4], atomic radius[5], and solid solubility[6] between alloying elements and the Al matrix, the degree of lattice distortion caused by these elements varies, leading to different effects on TC. Alloying elements with greater difference in valence state have a more pronounced impact on TC. This difference in valence state alters the Brillouin zone of the matrix, either expanding or compressing it, which disrupts the periodic lattice structure, increases lattice distortion, and subsequently reduces TC[7]. The mismatch of Al and other atoms caused by difference in atom radii also disrupts the periodicity of the lattice, thus increasing the scattering of electrons[8]. The addition of Ce (atom radius = 0.183 nm), which has a larger atomic radius than Al (atom radius = 0.143 nm), can reduce the lattice distortion caused by the addition of Fe (atom radius = 0.127 nm) and Si (atom radius = 0.134 nm). This reduction in lattice distortion can create more paths for electron transition, thus improving the TC[9]. In addition, the content and morphology of secondary phases significantly affect the TC and strength of Al alloys. Highly continuous secondary phases impede electron transfer, thereby reducing the mean free path of electron migration and resulting in lower TC[10,11].

The lattice distortion and formation of secondary phases introduced by alloying elements can cause solid solution strengthening and precipitation strengthening in Al alloys. An additive model is commonly used to evaluate the contributions of individual elements to solid solution strengthening[12]: σ = ∑kiCi2/3, where ki is the scale coefficient of the ith alloying element and Ci represents its mass fraction. The scale coefficients of alloying elements are different[10,11], such as kZn = 3 MPa/wt.%-2/3, kMg = 29 MPa/wt.%-2/3, and kSi = 66.3 MPa/wt.%-2/3. In Al-Si alloys, fragmentation of the secondary phase reduces the size of eutectic silicon, enhancing its precipitation strengthening effect in the alloy[13]. Additionally, the spherical Si phase reduces stress concentration and prolongs the path of crack propagation, thereby enhancing the strength of Al alloys[14]. Considering the synergetic effects on TC and UTS caused by alloying elements, designing Al alloys with both high UTS and high TC through a bottom-up approach remains a significant challenge.

Machine learning (ML) has become popular in materials science research[15,16]; in particular, ML has been utilized for property prediction[17-19] and alloy design[20-22] of Al alloys. By using ML techniques, researchers can accelerate the process of predicting critical material properties, such as fracture toughness[23], corrosion resistance[24], and wear behaviour[25], with high accuracy and efficiency. Various ML algorithms such as support vector machine (SVM), tree ensembles and neural networks are used to establish separate models for predicting the performance of Al alloys with high precision[21]. Composition design and process parameter optimization based on the separate ML predicting models has proven to be an effective strategy for enhancing the performance of cast Al alloys across multiple dimensions, including hardness, strength, and modulus[26-29]. This approach enables the simultaneous optimization of multiple properties, thereby pushing the boundaries of alloy design toward higher application requirements. In addition, multi-objective optimization can also achieve a trade-off between conflicting performances. However, multi-objective optimization requires a large amount of data and accurate performance prediction models on a certain alloy series[18,21,30]. Insufficient data scale or quality can result in inaccurate outcomes during multi-objective optimization[31]. Regarding the input features, feature expansion and selection play crucial roles in incorporating physical parameters into prediction models and identifying the most significant features. Various atomic descriptors, such as atomic radius, electronegativity, modulus, and melting point, are commonly employed to enhance input features, thereby improving model interpretability[32]. Feature selection methods, including Lasso, Gini impurity, and correlation coefficients, are essential for identifying the most important features from an extensive set of expanded features. This process reduces model complexity and minimizes prediction errors[33].

This paper aims to use ML to design cast Al alloys with both high TC and ultimate tensile strength (UTS). Physical descriptors of the composition were added to the input feature list, followed by feature engineering to determine the optimal feature sets. ML models for predicting UTS and TC were developed separately. Guided by these models, a new Al alloy was designed, fabricated, and tested. The strength and TC closely align with the model predictions, and the underlying mechanisms are analyzed.

METHODS

We performed data collection, feature calculation, feature selection, prediction model development, new alloy design and validation [Figure 1]. Firstly, 277 as-cast Al alloys were collected from published papers one by one manually to ensure no mistakes occurred during data collection to establish an initial dataset [Supplementary Materials]. Data were only collected for cast Al alloys with no other processing techniques such as wrought or coating. The dataset included information about alloy composition, processing parameters of solution treatment and aging (i.e., time and temperature), TC, and UTS values. Table 1 shows a few sample data[34-36]. The alloy composition includes 22 elements (Si, Fe, Cu, B, Bi, Pb, Zn, Mn, Mg, Sn, Ti, V, Mo, Ni, Ce, Co, Cr, La, Sc, Sr, Zr, and Al) and their contents are given in wt.%. The processing parameters include the solution temperature [denoted as sol_T (oC)], solution time [denoted as sol_time (h)], quench temperature [denoted as quench_T (oC)], aging temperature [denoted as aging_T (oC)], and aging time [denoted as aging_time (h)]. Data format for the columns is all numeric and consistent. No outliers are identified from the dataset and no data were deleted. The missing values of processing parameters were replaced by -1. Figure 2 shows the distribution of UTS and TC of the dataset. The UTS values range from 50 to 350 MPa; the TC values range from 100 to 220 W·m-1·K-1.

Machine learning driven design of high-performance Al alloys

Figure 1. Procedure of Al alloys design by ML. ML: Machine learning.

Machine learning driven design of high-performance Al alloys

Figure 2. The UTS and TC of the 277 data in the dataset. UTS: Ultimate tensile strength; TC: thermal conductivity.

Table 1

Sample data in the dataset

Compositionsol_T
(°C)
sol_time
(h)
quench_T
(°C)
aging_T
(°C)
aging_time
(h)
UTS
(MPa)
TC
(W·m-1·K-1)
Ref.
Al-8Si-0.512Mg-0.55Fe-0.08Sr-0.01Cu5350.5501703304171[34]
Al-8Si-0.512Mg-0.55Fe-0.08Sr-0.01Cu5354501703294163[34]
Al-5Si-2Cu-2Mg5006.5852504249169[35]
Al-5Si-2Cu-2Mg-0.05Zr5006.5852504228163[35]
Al-5Si-2Cu-2Mg-0.1Zr5006.5852504226167[35]
Al-5Si-2Cu-2Mg-0.12Zr5006.5852504230171[35]
Al-5Si-2Cu-2Mg-0.19Zr5006.5852504210165[35]
Al-10.5Si-1.75Cu-0.76Zn-0.23Mg4900.25502201312155[36]
Al-10.5Si-2.43Cu-0.76Zn-0.24Mg4900.25502200.5349152[36]

To explore the composition information, physical descriptors must be added[37,38] to expand the feature list. A total of 42 physical parameters of elements were exported from the Materials Project[39], which are listed in Table 2. From the alloy composition, the average and variance of each parameter were then used as input features:

$$ p_{mean}=\sum_{i=1}^{n}c_ip_i $$

$$ p_{std}=\sqrt{\sum_{i=1}^{n}\frac{(c_ip_i-p_{mean})^2}{n}} $$

Table 2

42 physical parameters of elements

NameDefinition
aCell parameter (pm)
bCell parameter (pm)
cCell parameter (pm)
ANAtomic number
ARAtomic radius (pm)
BBulk modulus (GPa)
BIPTBlock in periodic table
BPBoiling point (K)
CSpecific heat (J/K*mol)
CRCovalent radius (pm)
DSDensity of solid (g/cm3)
EYoung’s modulus (GPa)
E0The change in enthalpy of a substance from 0 to 298 K (kJ/mol)
EAElectron affinity (kJ/mol)
ENAEnthalpy of atomization (kJ/mol)
ENFEnthalpy of fusion (kJ/mol)
ENVEnthalpy of vaporization (kJ/mol)
FIEFirst ionization energies (kJ/mol)
GShear modulus (GPa)
GIPTGroup in periodic table
LAngular quantum number
MMagnetic quantum number
MPMelting point (K)
MVMolar volume (cm3)
NPrincipal quantum number
PEPauling electronegativity
PIPTPeriod in periodic table
PRPoisson ratio
RAMRelative atomic mass
S0Standard entropy (J/K*mol)
SESanderson electronegativity
SIESecond ionization energies (kJ/mol)
SOLSolid solubility in Al (wt.%)
TIEThird ionization energies (kJ/mol)
VENumber of valence electrons
VEDNumber of valence electrons in the d orbital
VEFNumber of valence electrons in the f orbital
VEPNumber of valence electrons in the p orbital
VESNumber of valence electrons in the s orbital
VRVan der Waals radius (pm)
VSValence state
WFWork function (eV)

where ci is the content of the element (wt.%) and the pi is the physical parameter of the element. The initial list contains 111 features, including 22 composition features, 84 physical descriptors and five processing features.

Subsequently, two feature selection methods based on Lasso and Gini impurity were employed to identify the optimal feature list for building ML models. Tree ensemble and SVM algorithms were used to predict TC and UTS, with a training-testing split ratio of 85% to 15%. The R2 and root mean square error (RMSE) metrics are used to evaluate the accuracy of the ML models:

$$ \mathrm{R^2}=1-\frac{\sum_{i=1}^{n}(y_i-\hat{y}_i)^2}{\sum_{i=1}^{n}(y_i-\bar{y}_i)^2} $$

$$ RMSE=\sqrt{\frac{1}{n}\sum_{i=1}^{n}(y_i-\hat{y}_i)^2} $$

where n is the number of data in the training/test set, yi is the actual value of the ith data, $$ \hat{y}_i $$ is the predicted value and $$ \bar{y}_i $$ is the average of the actual values, respectively. The better prediction tends to have lower root mean squared error (RMSE) and higher R2. Finally, a new alloy with improved properties was designed based on the prediction models and validated through experiments.

RESULTS AND DISCUSSION

Feature engineering and ML

Choosing the appropriate features is necessary to establish reliable ML models, especially for a dataset with only 277 data. The removal of unimportant features can reduce the calculation complexity and enhance the prediction accuracy. The Lasso and Gini impurity selection are popular methods for feature selection. The Lasso algorithm[40] adds the L1 regularization term into the loss function of linear regression:

$$ Loss(y_i,\hat{y}_i)=\sum_{i=1}^{n}(y_i-\hat{y}_i)^2+\alpha |w| $$

where yi is the actual value of the ith data, $$ \hat{y}_i $$ is the predicted value, α is the penalty coefficient and |w| is the sum of the absolute values of the feature coefficients. Feature coefficient refers to the coefficient assigned to each feature in linear regression. Features having larger coefficients tend to be more important. In the process of minimizing the loss function, the coefficients of irrelevant features will shrink to 0. As the penalty coefficient α increases, more feature coefficients are reduced to zero, minimizing |w|. This process retains important features with non-zero coefficients while eliminating unimportant ones. In Figure 3, the number of features with non-zero coefficients, indicating their importance, gradually decreases with increasing α. For the TC prediction, α = 0.0133 was selected, and for the UTS prediction, α = 0.0447 was chosen, leaving 56 features. This threshold, where half of the features are retained, is commonly used in feature selection. These 56 features with non-zero coefficients are ultimately selected for further analysis[41,42].

Machine learning driven design of high-performance Al alloys

Figure 3. The number of features with non-zero coefficient decreases with the increase of α in the (A) TC dataset and (B) UTS dataset. TC: Thermal conductivity; UTS: ultimate tensile strength.

Gini impurity[43], which reflects the uncertainty reduction after branching in tree models, is a common index to measure the feature importance in the prediction using tree algorithms. The feature will be more important when the prediction uncertainty reduces more after its inclusion. Three different tree algorithms including random forest (RF), eXtreme gradient boosting (XGBoost) and gradient boosting decision tree (GBDT) are used to calculate the Gini impurity of every feature. The average of feature importance calculated by these three algorithms is ranked in Figure 4, with the 26 most important features remaining as the input of performance prediction.

Machine learning driven design of high-performance Al alloys

Figure 4. The feature importance ranking of (A) the TC features and (B) the UTS features. TC: Thermal conductivity; UTS: ultimate tensile strength.

Normalization was applied before the UTS prediction but not for the TC prediction:

$$ \bar{X}=\frac{X-\mu}{\sigma} $$

where $$ \bar{X} $$ is the normalized data, X is the raw data, μ is the average value of the raw data and σ is the standard variance of the raw data. In tree ensemble algorithms, normalization does not affect the division of branch nodes, as the information gain is independent of data distribution. However, for the SVM algorithm, variations in the scale of different variables can significantly influence the calculation results and reduce prediction accuracy.

To prove the necessity of feature expansion and selection, the model accuracy adopting different features is compared. The XGBoost algorithm is used to predict TC and the SVM algorithm is used to predict UTS, with four types of features as the input. As shown in Figures 5-7, when only composition information containing 22 elements is used as the model input, the prediction has the lowest accuracy. The accuracy of TC and UTS prediction improves substantially from 0.68 (composition only) to 0.82 (composition + processing). The prediction accuracy further increases after feature expansion. After feature selection by Lasso and Gini impurity algorithm, the R2 of TC and UTS prediction are both above 0.9.

Machine learning driven design of high-performance Al alloys

Figure 5. The comparison of predicted and actual TC using XGBoost algorithm and input of (A) composition information, (B) composition and processing parameter information, (C) composition and processing parameter information with feature expansion (D) composition and processing parameter information with feature expansion and selection. TC: Thermal conductivity; XGBoost: eXtreme gradient boosting.

Machine learning driven design of high-performance Al alloys

Figure 6. The comparison of predicted and actual UTS using SVM algorithm and input of (A) composition information, (B) composition and processing parameter information, (C) composition and processing parameter information with feature expansion, (D) composition and processing parameter information with feature expansion and selection. UTS: Ultimate tensile strength; SVM: support vector machine.

Machine learning driven design of high-performance Al alloys

Figure 7. The R2 and RMSE of (A) TC and (B) UTS using different features as input. RMSE: Root mean squared error; TC: thermal conductivity; UTS: ultimate tensile strength.

Considering two performance prediction models have been established, the optimization of the as-cast Al alloy composition is necessary. Because the processing parameters have numerous missing values in the dataset, the following heat treatment parameters are used: solution treatment at 500 °C for 6 h and aging at 250 °C for 4 h, which is the most frequently used heat treatment condition in the dataset. Since Si, Mg, Zn, and Cu are the most common alloying elements, 800 virtual Al-Si-Mg-Zn-Cu alloy compositions are generated randomly, and TC and UTS values are predicted by the models. As shown in Figure 8, among the 800 virtual samples, a sample with the composition of Al-2.64Cu-0.43Mg-0.10Zn-0.03Si has high predicted values for both TC and UTS.

Machine learning driven design of high-performance Al alloys

Figure 8. Predicted TC and UTS values of 800 virtual samples generated by two models. TC: Thermal conductivity; UTS: ultimate tensile strength.

Experiment validation

According to the recommended composition, the alloy was fabricated by commercial-purity Al (99.95%), Mg (99.95%), Zn (99.95%), Mg-10 wt.% Si, and Mg-10 wt.% Cu master alloys. The raw materials were melted in an electric resistance furnace at 720 °C. The molten alloy was stirred manually and held for homogenization, and then cast into a cylinder ingot with Φ = 60 mm. The ingots were solution-treated at 500 °C for 6 h and aged at 250 °C for 4 h.

Three dog-bone-shaped tensile specimens with dimensions of 18 (L) mm × 3.4 (W) mm × 2 (T) mm were cut from the ingots. Tensile tests were conducted using a Zwick-100 kN instrument with a BT2-EXMACWD at a constant strain rate of 1.0 × 10-4·s-1. The TC λ was calculated by λ = ραCp[44] where ρ is the density of Al (2.7 g·cm-3), α is the thermal diffusivity, Cp is the specific heat capacity of Al (0.88 kJ·kg-1·K-1). The thermal diffusivity α was measured three times for each specimen (Ф 12.7 × H 2.0 mm) at room temperature (25 °C) using the laser transient TC meter (LFA467HT, Netzsch).

The predicted and actual values obtained by strength and TC tests are listed in Table 3 and the tensile stress-strain curve is shown in Figure 9. The relative errors for TC and UTS predictions are 5.9% and 5.1%, respectively. As shown in Figure 10[45-48], compared to other as-cast alloys reported in the literature, the Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy has TC > 190 W·m-1·K-1 and UTS > 220 MPa, making it a good candidate material when both strength and TC are required.

Machine learning driven design of high-performance Al alloys

Figure 9. The tensile stress-strain curve of Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy.

Machine learning driven design of high-performance Al alloys

Figure 10. TC and UTS values of Al-2.64Si-0.43Mg-0.10Zn-0.03Cu compared with other alloys in the literature[45-48]. TC: Thermal conductivity; UTS: ultimate tensile strength.

Table 3

The predicted and actual values of TC and UTS of the Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy

Predicted valueActual valueRelative error
TC179.7 W·m-1·K-1191.0 W·m-1·K-15.9%
UTS209.8 MPa221.0 MPa5.1%

X-ray diffraction (XRD) analysis was conducted for the Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy to determine the phase composition. As shown in Figure 11A, apart from Al peaks, only diffraction peaks of Si are present in the alloy. Figure 11B and C shows the optical micrograph (OM) and scanning electron microscopy (SEM) of the Al-2.64Si-0.43 Mg-0.10Zn-0.03Cu alloy. The microstructure of the alloy consists of primary α-Al cells, with spherical Si particles along with a few non-spherical Si particles. The energy-dispersive X-ray spectroscopy (EDS) results also confirm the XRD results. As shown in Figure 11D, Cu, Zn and Mg elements exist as solutes in Al, while the Si element is found in the secondary phase.

Machine learning driven design of high-performance Al alloys

Figure 11. (A) XRD patterns (B) OM (C) SEM micrograph (D) EDS maps of the Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy. XRD: X-ray diffraction; OM: optical micrograph; SEM: scanning electron microscopy; EDS: energy-dispersive X-ray spectroscopy.

The formation of Si secondary phase reduces the Si solute concentration in Al lattice. Because of the significant atomic radius difference between the Al atom (RAl = 118 pm) and the Si atom (RSi = 143 pm), Si solutes significantly reduce TC of Al alloys[49]. The precipitation of Si reduces the amount of Si solutes in the Al matrix, resulting in higher TC[50].

The morphology of the secondary phase also influences TC. Continuous secondary phases reduce the average free path of electrons[51], an effect that becomes more pronounced as the size of the secondary phase increases[52]. In the current alloy, the Si particles are predominantly spherical and exhibit discontinuous interfaces, allowing electrons to travel longer distances within the Al matrix[53]. As a result, TC is less adversely impacted[54].

The yield strength, σy, of Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy can be expressed as:

$$ \sigma_y=\sigma_0+\sigma_{ss}+\sigma_{gs}+\sigma_{PPT} $$

where σ0 is the yield stress of pure Al (35 MPa[55]), σss is the solid-solution strengthening, σgs is the grain size strengthening, and σPPT is the precipitation strengthening.

Solid-solution strengthening, σss, can be calculated as the sum of the individual effects of each alloying element on strength enhancement, which is expressed by:

$$ \sigma_{ss}=\sum_ik_iC_i $$

where ki is the contributing factor of alloying element (kSi = 9.3 MPa/at.%, kCu = 16.2 MPa/at.%, kMg = 17.2 MPa/at.%[56] and kZn = 2.9 MPa/at.%[57]). Due to the low solid solubility of Si in Al, the σss value is approximately 6.9 MPa.

The strength contribution from grain size strengthening σgs was calculated using the Hall–Petch equation[58]:

$$ \sigma_{gb}=k\cdot d^{-\frac{1}{2}} $$

where k is a constant (0.06 MPa·m-1/2 for Al alloys[59]) and d is the grain size. The σgb value of Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy is 6.7 MPa based on the average grain size (~80 μm).

Considering the yield stress of ~183 MPa in the Al-2.64Si-0.43Mg-0.10Zn-0.03Cu alloy, precipitation strengthening is likely to be important. The fragmented eutectic Si particles provide only a limited contribution to overall strengthening. It has been reported that eutectic Si particles with a radius of ~2 μm and a volume fraction of ~6% contribute around 4 MPa to the strength[60]. In contrast, Si nanoprecipitates and solute clusters formed during the aging process can significantly enhance the strength[60,61]. It has been shown that nanoscale Si particles and clusters, with radii ranging from 1 to 10 nm, provide strong Orowan strengthening, exceeding 100 MPa[62]. Additionally, nanoscale Si particles can act as dislocation pinning sites, leading to dislocation accumulation and further contributing to dislocation strengthening[63].

Key factors affecting TC and UTS

The three most important alloying elements affecting TC and UTS are listed in Table 4, in which Mg, Si, and Fe have the greatest impact on TC and Mn, and Cu and Zn have the greatest impact on UTS. Influence levels of alloying elements on TC of Al alloys depend on the physical parameters of these elements, such as valence electrons, atom radius difference, and so on[64]. Due to the high solid solubility of Mg in Al (15.9 wt.%), Mg elements generally exist as solutes in Al alloys, avoiding the weakening of TC caused by the formation of secondary phases. Compared to Mg (3s2) atoms, there are vacancies in the valence electron configuration of Fe (3d64s2) and Si (3s23p2) atoms, allowing them to more readily absorb free electrons during heat transfer and reduce the TC[65]. Due to the low solubility of Si and Fe at room temperature, almost all Fe and Si are precipitated as Al13Fe4 and eutectic Si. The thickness of Al13Fe4 precipitates in Al–Fe alloys is significantly smaller than that of Si precipitates in Al–Si alloys[66], resulting in a greater impact on TC with the addition of Si.

Table 4

The three most important alloying elements affecting TC and UTS

TCUTS
MgMn
SiCu
FeZn

Mn usually exists as Al6Mn phases, which can improve the strength of the alloy by stabilizing the precipitation phases[67]. Cu acts as solution atom and forms Al2Cu phase, which can generate both solid solution strengthening and precipitation strengthening. In Al-Zn-Mg alloys, when the Cu content is below 3 wt.%, both hardness and strength exhibit an increase with rising Cu concentration[68]. Due to the small difference in atomic radius between Zn (R = 0.139 nm) and Al (R = 0.143 nm), the solid solution strengthening effect contributed by the addition of Zn is insignificant. Zn is commonly added with Mg to form MgZn2 or T-Mg32(Al,Zn)49, which contributes to precipitation strengthening[69]. A higher Zn/Mg ratio leads to the formation of smaller and denser the precipitates during the aging process, enhancing the mechanical properties of the alloy[70].

CONCLUSIONS

In this work, we established ML models for predicting TC and UTS of as-cast Al alloys. The feature expansion and feature selection using Lasso and Gini impurity took more physical and chemical factors into consideration and significantly improve the prediction accuracy. The R2 for the prediction of TC and UTS are above 0.9. An alloy with the composition of Al-2.64Cu-0.43Mg-0.10Zn-0.03Si alloy is recommended by the models. The alloy was fabricated, and it exhibits TC > 190 W·m-1·K-1 and UTS > 220 MPa, which are consistent with the model prediction. The microstructure analysis indicates that the alloy contains fragmented and spherical precipitates which reduce the electron scattering and offer precipitates strengthening, thereby improving the TC and UTS.

DECLARATIONS

Authors’ contributions

Writing - original draft, methodology, software, validation, formal analysis: Lu Z

Writing - review and editing, supervision, conceptualization: Kapoor I

Investigation: Li Y

Methodology: Liu Y

Supervision, resources, project administration: Zeng X

Writing - review and editing, supervision, conceptualization: Wang L

Availability of data and materials

The original data is provided in the Supplementary Materials.

Financial support and sponsorship

This work was supported by SJTU-Warwick Joint Seed Fund 2023/24 (SJTU2308), Shenzhen Science and Technology Program (KJZD20231023092902005), and UK Engineering and Physical Sciences Research Council Impact Acceleration Account (G.ESWM.0730.EXP).

Conflicts of interest

All authors declared that there are no conflicts of interest.

Ethical approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Copyright

© The Author(s) 2024.

Supplementary Materials

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Cite This Article

Research Article
Open Access
Machine learning driven design of high-performance Al alloys
Ziliang Lu, ... Leyun Wang

How to Cite

Lu, Z.; Kapoor I.; Li Y.; Liu Y.; Zeng X.; Wang L. Machine learning driven design of high-performance Al alloys. J. Mater. Inf. 2024, 4, 19. http://dx.doi.org/10.20517/jmi.2024.21

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