Heterogeneous Structure and Mechanical Properties of Strong and Tough Al Alloys Prepared by Selective Laser Melting

doi:10.11900/0412.1961.2022.00314

Acta Metall Sin

2022, Vol. 58

Issue (11): 1509-1518 DOI: 10.11900/0412.1961.2022.00314

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Heterogeneous Structure and Mechanical Properties of Strong and Tough Al Alloys Prepared by Selective Laser Melting

LIN Yan¹, SI Cheng¹, XU Jingyu¹, LIU Ze², ZHANG Cheng¹(

), LIU Lin¹

^1.State Key Lab for Materials Processing and Die & Mold Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
^2.Department of Engineering Mechanics, School of Civil Engineering, Wuhan University, Wuhan 430072, China

Cite this article:

LIN Yan, SI Cheng, XU Jingyu, LIU Ze, ZHANG Cheng, LIU Lin. Heterogeneous Structure and Mechanical Properties of Strong and Tough Al Alloys Prepared by Selective Laser Melting. Acta Metall Sin, 2022, 58(11): 1509-1518.

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Abstract

Aluminum alloys have been widely used in fields such as automotive and aerospace industries, owing to their excellent mechanical properties, lightweight, and low recycling costs. However, aluminum alloys processed by selective laser melting (SLM) typically suffer from insufficient strength and fracture toughness. To tackle this issue, a new strategy that integrates eutectic composition design and grain refinement has been adopted to create a heterogeneous structure that can improve strength and toughness of SLMed Al-Fe-Zr alloys. The SLMed AlFe₅ alloy consists of high-volume-fraction of coarse and columnar grains and low-volume-fraction of fine grains, and no obvious heterogeneity is visible across the microstructure length scale. With the addition of Zr, the volume fraction of fine grains significantly increases, leading to the heterogeneous distribution of coarse and fine grains in the SLMed AlFe₅Zr₁ alloy. Meanwhile, both AlFe₅ and AlFe₅Zr₁ alloys show a nanoscale cellular structure. This type of a nanosized cellular structure, together with supersaturated Fe and high-density dislocations, contributes to a high yield strength of 400 MPa for the SLMed AlFeZr alloys. The heterogeneous structure can further improve the strain strengthening capability, enabling a tensile strength as high as 450 MPa for the AlFe₅Zr₁ alloy. Furthermore, the heterogeneous structure promotes crack deflection and crack tip blunting, which can effectively increase crack growth resistance and impart superior fracture toughness to the AlFe₅Zr₁ alloy.

Key words: Al-Fe-Zr alloy selective laser melting (SLM) heterogeneous structure mechanical property

Received: 23 June 2022

ZTFLH:

TG146.2

Fund: National Natural Science Foundation of China(52061160483);National Natural Science Foundation of China(92166130);National Natural Science Foundation of China(52001075);China Postdoctoral Science Foundation(2021M701290)

About author: ZHANG Cheng, associate professor, Tel: (027)87558200, E-mail: czhang@hust.edu.cn

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https://www.ams.org.cn/EN/10.11900/0412.1961.2022.00314 OR https://www.ams.org.cn/EN/Y2022/V58/I11/1509

Fig.1 Schematics of the plate tensile (a) and the single-edge-notch tension (b) specimens (unit: mm. L—length of specimen, B—thickness of specimen, W—width of specimen, a—length of crack)

Fig.2 Relative densities of SLMed AlFe₅Zr₁ alloy with different processing parameters (a), and reconstructed 3D X-ray computed tomography (CT) image representing porosity distribution within the AlFe₅Zr₁ alloy prepared with the best SLM processing procedure (b) (SLM—selective laser melting)

Fig.3 EBSD images (a, b), pole figures (c, d), and grain size distributions (e) of SLMed AlFe₅ (a, c) and AlFe₅Zr₁ (b, d) alloys

Fig.4 Bright-field TEM images (a, c), high-angle annular dark field (HAADF) images (left) and corresponding EDS element mappings of rectangle (right) (b, d) of SLMed AlFe₅ (a, b) and AlFe₅Zr₁ (c, d) alloys (Inset in Fig.4c shows the corresponding selected area electron diffraction (SAED) pattern)

Fig.5 Room temperature quasi-static tensile engineering stress-strain curves of the SLMed AlFe₅, AlFe₅Zr₁, and AlSi₁₀Mg alloys

Table 1 Tensile properties of the SLMed AlFe₅, AlFe₅Zr₁, and AlSi₁₀Mg alloys

Fig.6 Load-displacement curves of the SLMed AlFe₅, AlFe₅Zr₁, and AlSi₁₀Mg alloys

Fig.7 Bright-field TEM images showing tension-induced microstructure evolution in the SLMed AlFe₅Zr₁ alloy

Fig.8 Crack profiles characterized on the surface of the SLMed AlFe₅Zr₁ alloy at different stages of crack extension (a-d), and 3D fracture surface morphologies for the SLMed AlFe₅Zr₁ (e) and AlFe₅ (f) alloy samples after fracture toughness testing
(a) 270 N (b) 275 N (c) 290 N (d) 295 N

1	Wong K V, Hernandez A. A review of additive manufacturing [J]. Int. Schol. Res. Not., 2012, 2012: 208760
2	Frazier W E. Metal additive manufacturing: A review [J]. J. Mater. Eng. Perform., 2014, 23: 1917 doi: 10.1007/s11665-014-0958-z
3	Herzog D, Seyda V, Wycisk E, et al. Additive manufacturing of metals [J]. Acta Mater., 2016, 117: 371 doi: 10.1016/j.actamat.2016.07.019
4	Lewandowski J J, Seifi M. Metal additive manufacturing: A review of mechanical properties [J]. Annu. Rev. Mater. Res., 2016, 46: 151 doi: 10.1146/annurev-matsci-070115-032024
5	Wang Y M, Voisin T, McKeown J T, et al. Additively manufactured hierarchical stainless steels with high strength and ductility [J]. Nat. Mater., 2018, 17: 63 doi: 10.1038/nmat5021 pmid: 29115290
6	Barriobero-Vila P, Gussone J, Stark A, et al. Peritectic titanium alloys for 3D printing [J]. Nat. Commun., 2018, 9: 3426 doi: 10.1038/s41467-018-05819-9 pmid: 30143641
7	Sun Z J, Tan X P, Tor S B, et al. Simultaneously enhanced strength and ductility for 3D-printed stainless steel 316L by selective laser melting [J]. NPG Asia Mater., 2018, 10: 127 doi: 10.1038/s41427-018-0018-5
8	Zhang D Y, Qiu D, Gibson M A, et al. Additive manufacturing of ultrafine-grained high-strength titanium alloys [J]. Nature, 2019, 576: 91 doi: 10.1038/s41586-019-1783-1
9	Mishra R S, Thapliyal S. Design approaches for printability-performance synergy in Al alloys for laser-powder bed additive manufacturing [J]. Mater. Des., 2021, 204: 109640 doi: 10.1016/j.matdes.2021.109640
10	Rometsch P, Jia Q B, Yang K V, et al. Aluminum alloys for selective laser melting—Towards improved performance [A]. Additive Manufacturing for the Aerospace Industry [M]. Amsterdam: Elsevier, 2019: 301
11	Todd I. No more tears for metal 3D printing [J]. Nature, 2017, 549: 342 doi: 10.1038/549342a
12	Aboulkhair N T, Simonelli M, Parry L, et al. 3D printing of aluminium alloys: Additive manufacturing of aluminium alloys using selective laser melting [J]. Prog. Mater. Sci., 2019, 106: 100578 doi: 10.1016/j.pmatsci.2019.100578
13	Prashanth K G, Scudino S, Eckert J. Defining the tensile properties of Al-12Si parts produced by selective laser melting [J]. Acta Mater., 2017, 126: 25 doi: 10.1016/j.actamat.2016.12.044
14	Martin J H, Yahata B D, Hundley J M, et al. 3D printing of high-strength aluminium alloys [J]. Nature, 2017, 549: 365 doi: 10.1038/nature23894
15	Spierings A B, Dawson K, Kern K, et al. SLM-processed Sc-and Zr-modified Al-Mg alloy: Mechanical properties and microstructural effects of heat treatment [J]. Mater. Sci. Eng., 2017, A701: 264
16	Jia Q B, Rometsch P, Kürnsteiner P, et al. Selective laser melting of a high strength AlMnSc alloy: Alloy design and strengthening mechanisms [J]. Acta Mater., 2019, 171: 108 doi: 10.1016/j.actamat.2019.04.014
17	Li R D, Wang M B, Li Z M, et al. Developing a high-strength Al-Mg-Si-Sc-Zr alloy for selective laser melting: Crack-inhibiting and multiple strengthening mechanisms [J]. Acta Mater., 2020, 193: 83 doi: 10.1016/j.actamat.2020.03.060
18	Pham M S, Dovgyy B, Hooper P A, et al. The role of side-branching in microstructure development in laser powder-bed fusion [J]. Nat. Commun., 2020, 11: 749 doi: 10.1038/s41467-020-14453-3
19	Zhu Z G, Ng F L, Seet H L, et al. Superior mechanical properties of a selective-laser-melted AlZnMgCuScZr alloy enabled by a tunable hierarchical microstructure and dual-nanoprecipitation [J]. Mater. Today, 2022, 52: 90 doi: 10.1016/j.mattod.2021.11.019
20	Liu Y G, Zhang J Q, Tan Q Y, et al. Additive manufacturing of high strength copper alloy with heterogeneous grain structure through laser powder bed fusion [J]. Acta Mater., 2021, 220: 117311 doi: 10.1016/j.actamat.2021.117311
21	Li Y, Chen K, Narayan R L, et al. Multi-scale microstructural investigation of a laser 3D printed Ni-based superalloy [J]. Addit. Manuf., 2020, 34: 101220
22	Liu L X, Pan J, Zhang C, et al. Achieving high strength and ductility in a 3D-printed high entropy alloy by cooperative planar slipping and stacking fault [J]. Mater. Sci. Eng., 2022, A843: 143106
23	Wu X L, Yang M X, Yuan F P, et al. Heterogeneous lamella structure unites ultrafine-grain strength with coarse-grain ductility [J]. Proc. Natl. Acad. Sci. USA, 2015, 112: 14501 doi: 10.1073/pnas.1517193112
24	Ma E, Zhu T. Towards strength-ductility synergy through the design of heterogeneous nanostructures in metals [J]. Mater. Today, 2017, 20: 323 doi: 10.1016/j.mattod.2017.02.003
25	Wang Y M, Chen M W, Zhou F H, et al. High tensile ductility in a nanostructured metal [J]. Nature, 2002, 419: 912 doi: 10.1038/nature01133
26	Lin Y, Pan J, Zhou H F, et al. Mechanical properties and optimal grain size distribution profile of gradient grained nickel [J]. Acta Mater., 2018, 153: 279 doi: 10.1016/j.actamat.2018.04.065
27	Thapliyal S, Shukla S, Zhou L, et al. Design of heterogeneous structured Al alloys with wide processing window for laser-powder bed fusion additive manufacturing [J]. Addit. Manuf., 2021, 42: 102002
28	Tada H, Paris P C, Irwin G R. The Stress Analysis of Cracks [M]. Hellertown: Dell Research Corporation, 1973: 34
29	Roth C C, Tancogne-Dejean T, Mohr D. Plasticity and fracture of cast and SLM AlSi10Mg: High-throughput testing and modeling [J]. Addit. Manuf., 2021, 43: 101998
30	Wu J, Wang X Q, Wang W, et al. Microstructure and strength of selectively laser melted AlSi10Mg [J]. Acta Mater., 2016, 117: 311 doi: 10.1016/j.actamat.2016.07.012
31	Tucho W M, Cuvillier P, Sjolyst-Kverneland A, et al. Microstructure and hardness studies of Inconel 718 manufactured by selective laser melting before and after solution heat treatment [J]. Mater. Sci. Eng., 2017, A689: 220
32	Voisin T, Forien J B, Perron A, et al. New insights on cellular structures strengthening mechanisms and thermal stability of an austenitic stainless steel fabricated by laser powder-bed-fusion [J]. Acta Mater., 2021, 203: 116476 doi: 10.1016/j.actamat.2020.11.018
33	Wang H, Zhu Z G, Chen H S, et al. Effect of cyclic thermal loadings on the microstructural evolution of a cantor alloy in 3D printing processes [J]. Microsc. Microanal., 2019, 25: 2568 doi: 10.1017/S1431927619013576
34	Kou S. Welding Metallurgy [M]. 2nd Ed., Hoboken, New Jersey: John Wiley& Sons, Inc., 2003: 17
35	Prashanth K G, Eckert J. Formation of metastable cellular microstructures in selective laser melted alloys [J]. J. Alloys Compd., 2017, 707: 27 doi: 10.1016/j.jallcom.2016.12.209
36	Birnbaum A J, Steuben J C, Barrick E J, et al. Intrinsic strain aging, Σ3 boundaries, and origins of cellular substructure in additively manufactured 316L [J]. Addit. Manuf., 2019, 29: 100784
37	Bertsch K M, De Bellefon G M, Kuehl B, et al. Origin of dislocation structures in an additively manufactured austenitic stainless steel 316L [J]. Acta Mater., 2020, 199: 19 doi: 10.1016/j.actamat.2020.07.063
38	Petch N J. The cleavage strength of polycrystals [J]. J. Iron Steel Inst., 1953, 174: 25
39	Hall E O. The deformation and ageing of mild steel: III Discussion of results [J]. Proc. Phys. Soc., 1951, 64B: 747
40	Kamikawa N, Huang X X, Tsuji N, et al. Strengthening mechanisms in nanostructured high-purity aluminium deformed to high strain and annealed [J]. Acta Mater., 2009, 57: 4198 doi: 10.1016/j.actamat.2009.05.017
41	Wu Y Y, Zhang T M, Chen C, et al. Microstructure and mechanical property evolution of additive manufactured eutectic Al-2Fe alloy during solidification and aging [J]. J. Alloys Compd., 2022, 897: 163243 doi: 10.1016/j.jallcom.2021.163243
42	Thangaraju S, Heilmaier M, Murty B S, et al. On the estimation of true Hall-Petch constants and their role on the superposition law exponent in Al alloys [J]. Adv. Eng. Mater., 2012, 14: 892 doi: 10.1002/adem.201200114
43	Clausen B, Lorentzen T, Leffers T. Self-consistent modelling of the plastic deformation of f.c.c. polycrystals and its implications for diffraction measurements of internal stresses [J]. Acta Mater., 1998, 46: 3087 doi: 10.1016/S1359-6454(98)00014-7
44	Hansen N, Huang X. Microstructure and flow stress of polycrystals and single crystals [J]. Acta Mater., 1998, 46: 1827 doi: 10.1016/S1359-6454(97)00365-0
45	Hong Y J, Zhou C S, Zheng Y Y, et al. The cellular boundary with high density of dislocations governed the strengthening mechanism in selective laser melted 316L stainless steel [J]. Mater. Sci. Eng., 2021, A799: 140279
46	Chen B, Moon S K, Yao X, et al. Strength and strain hardening of a selective laser melted AlSi10Mg alloy [J]. Scr. Mater., 2017, 141: 45 doi: 10.1016/j.scriptamat.2017.07.025
47	Wang P, Gammer C, Brenne F, et al. Microstructure and mechanical properties of a heat-treatable Al-3.5Cu-1.5Mg-1Si alloy produced by selective laser melting [J]. Mater. Sci. Eng., 2018, A711: 562
48	Zhang X X, Andrä H, Harjo S, et al. Quantifying internal strains, stresses, and dislocation density in additively manufactured AlSi10Mg during loading-unloading-reloading deformation [J]. Mater. Des., 2021, 198: 109339 doi: 10.1016/j.matdes.2020.109339
49	Hu Z H, Qi Y, Nie X J, et al. The Portevin-Le Chatelier (PLC) effect in an Al-Cu aluminum alloy fabricated by selective laser melting [J]. Mater. Charact., 2021, 178: 111198 doi: 10.1016/j.matchar.2021.111198
50	Zhang X X, Knoop D, Andrä H, et al. Multiscale constitutive modeling of additively manufactured Al-Si-Mg alloys based on measured phase stresses and dislocation density [J]. Int. J. Plast., 2021, 140: 102972 doi: 10.1016/j.ijplas.2021.102972
51	Yang M X, Pan Y, Yuan F P, et al. Back stress strengthening and strain hardening in gradient structure [J]. Mater. Res. Lett., 2016, 4: 145 doi: 10.1080/21663831.2016.1153004
52	Li J J, Lu W J, Chen S H, et al. Revealing extra strengthening and strain hardening in heterogeneous two-phase nanostructures [J]. Int. J. Plast., 2020, 126: 102626 doi: 10.1016/j.ijplas.2019.11.005
53	Cotterell B, Rice J R. Slightly curved or kinked cracks [J]. Int. J. Fract., 1980, 16: 155 doi: 10.1007/BF00012619
54	Gludovatz B, Hohenwarter A, Catoor D, et al. A fracture-resistant high-entropy alloy for cryogenic applications [J]. Science, 2014, 345: 1153 doi: 10.1126/science.1254581 pmid: 25190791
55	Launey M E, Ritchie R O. On the fracture toughness of advanced materials [J]. Adv. Mater., 2009, 21: 2103 doi: 10.1002/adma.200803322
56	Ritchie R O. The conflicts between strength and toughness [J]. Nat. Mater., 2011, 10: 817 doi: 10.1038/nmat3115 pmid: 22020005
57	Lin Y, Yu Q, Pan J, et al. On the impact toughness of gradient-structured metals [J]. Acta Mater., 2020, 193: 125 doi: 10.1016/j.actamat.2020.04.027

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