High-strength Al-based Alloys

High-strength Al-based alloys

Contact: Prof. Dr. Julia Hufenbach, Dr. Uta Kühn

Aluminum alloys have become indispensable as lightweight construction material for industry, especially within the mobility sector. By applying additive manufacturing techniques, topology-optimized lightweight components can be realized in significantly reduced development times in comparison to conventional manufacturing routes. Our research activities do not only cover the fabrication of commercially available aluminum alloys by laser powder bed fusion (PBF-LB/M), e.g., AlSi12, AlSi10Mg and AA2024, but also the development of novel aluminum alloys tailored for additive manufacturing. Specifically, high-strength aluminum alloys, e.g., AA2024 or AA7075, are prone to hot cracking which is a challenge in the manufacturing via PBF‑LB/M. This requires the design of new aluminum alloys, such as Al-Mn-Ce- and Al-Mg-Zr-based systems, that combine the desired mechanical properties with improved processability.

One approach to overcoming this challenge is the development of a novel high-strength Al-Mn-Ce alloy for powder-based additive manufacturing. The starting point for the research work is an Al₉₂Mn₆Ce₂ alloy that is composed of a metastable, high-strength Al₂₀Mn₂Ce phase in combination with a ductile Al matrix (Fig. 1). This leads to promising behaviour under compressive stress and high wear resistance. In follow-up studies, novel Al-Mn-Ce-Zr alloys with improved ductility under tensile loading and enhanced processability by PBF-LB/M were developed.
We acknowledge the German Research Foundation (DFG) for funding this project (Project number: 437911652).

In addition, rare-earth free Al-Mg-Zr-based alloys for robust processing of resilient and damage-tolerant materials by PBF-LB/M are being developed. The alloy design is supported by data-driven and experimental methods to accelerate the materials discovery. This is accompanied by cross-scale characterization in order to analyze the influence of the microstructure on the mechanical properties. By this approach, new Al-Mg-Zr-Si alloys have been developed, which can be used to manufacture resilient structures such as artificially designed mechanical metamaterials (see Fig. 2).
This work is supported by the DFG within the framework of the GRK 2868 D³ “Data‑Driven Design of Resilient Metamaterials” (Project number: 493401063).

Other points of interest in our research activities have been:

Effect of heat treatment on microstructure, mechanical properties, wear and behavior of the Al-based parts fabricated by LPBF.
Use of a second phase to improve the strength of both non heat-treatable and heat-treatable Al-based alloys. This has been typically done via the addition of TiB2 particles, which act as a grain refiner during LPBF.
Nanostructured high-strength Al-based LPBF alloys from amorphous powder precursors.

TEM image of a PBF-LB/M specimen showing the twinned Al20Mn2Ce phase and the Al-matrix.

Workflow chain. Backscatter electron image of tailored Al-powder, schematic illustration of PBF-LB/M process (P = laser power, v = laser scanning velocity, d = layer thickness, h = hatch distance), microstructure of PBF-LB/M printed Al-Mg-Si-Zr alloy that is recorded by electron backscatter diffraction method (including marked melt pools in the white dashed lines), and picture of a printed metamaterial with an architected structure of a spinodoid.

Publications

P. Grimm, L. Giebeler, J.K. Hufenbach, Harnessing centrifugal casting for designing aluminum alloys adapted to laser powder bed fusion, Journal of Materials Research and Technology, 39 (2025) 2118-2133

K. Gabrysiak, A. V. Boehm, T. Gustmann, C. Leyens, U. Kühn, Elevated-temperature strength and wear behavior of Al80Mn11Ce9 processed by laser powder bed fusion, Journal of Materials Research and Technology, 37 (2025) 2327-2337

K. Kosiba, T. Gustmann, J. T. Kim, J. Seok, J. Jung, L. Beyer, S. Scudino, L. Giebeler, J. Han, J. K. Hufenbach, Experimental cooling rates during high-power laser powder bed fusion at varying processing conditions, Journal of Alloys and Compounds, 967967(2023) 171773

U. Gebhardt, T. Gustmann, L. Giebeler, F. Hirsch, J. K. Hufenbach, M. Kästner, Additively manufactured AlSi10Mg lattices – Potential and limits of modelling as-designed structures, Materials & Design, 220 (2022) 110796

K. Gabrysiak, T. Gustmann, J. Freudenberger, K. Neufeld, L. Giebeler, C. Leyens, U. Kühn, Development and characterization of a metastable Al-Mn-Ce alloy produced by laser powder bed fusion, Additive Manufacturing Letters, 1 (2021) 100017.

P. Wang, S. Yu, J. Shergill, A. Chaubey, J. Eckert, K.G. Prashanth, S. Scudino: “Selective laser melting of Al-7Si-0.5Mg-0.5Cu: Effect of heat treatment on microstructure evolution, mechanical properties and wear resistance”, Acta Metallurgica Sinica (English Letters) 35 (2022) 389-396.

P. Wang, Y. Lei, J.-F. Qi, S.-J. Yu, R. Setchi, M.-W. Wu, J. Eckert, H.-C. Li, S. Scudino: “Wear behavior of a heat-treatable Al-3.5Cu-1.5 Mg-1Si alloy manufactured by selective laser melting”, Materials 14 (2021) 7048.

P. Wang, J. Eckert, K.G. Prashanth, M. Wu, I. Kaban, L. Xi, S. Scudino: “A review of particulate-reinforced aluminum matrix composites fabricated by selective laser melting”, Transactions of Nonferrous Metals Society of China 30 (2020) 2001-2034.

Z. Wang, S. Scudino, J. Eckert, K.G. Prashanth: “Selective laser melting of nanostructured Al-Y-Ni-Co alloy”, Manufacturing Letters 25 (2020) 21-25.

P. Wang, A. Gebert, L. Yan, H. Li, C. Lao, Z. Chen, K. Kosiba, U. Kühn, S. Scudino: “Corrosion behavior of Al-3.5Cu-1.5Mg-1Si alloy prepared by selective laser melting and heat treatment”, Intermetallics 124 (2020) 106871.

Y.D. Jia, L.B. Zhang, P. Ma, S. Scudino, G. Wang, J. Yi, J. Eckert, K.G. Prashanth: “Thermal expansion behavior of Al–xSi alloys fabricated using selective laser melting”, Progress in Additive Manufacturing 5 (2020) 247-257.

P. Wang, C.S. Lao, Z.W. Chen, Y.K. Liu, H. Wang, H. Wendrock, J. Eckert, S. Scudino: “Microstructure and mechanical properties of Al-12Si and Al-3.5Cu-1.5Mg-1Si bimetal fabricated by selective laser melting”, Journal of Materials Science & Technology 36 (2020) 18-26.

K.G. Prashanth, S. Scudino: “Quasicrystalline composites by additive manufacturing”, Key Engineering Materials 818 (2019) 72-76.

L. Xi, P. Wang, K.G. Prashanth, H. Li, H.V. Prykhodko, S. Scudino, I. Kaban: “Effect of TiB₂ particles on microstructure and crystallographic texture of Al-12Si fabricated by selective laser melting”, Journal of Alloys and Compounds 786 (2019) 551-556.

P. Wang, C. Gammer, F. Brenne, T, Niendorf, J. Eckert, S. Scudino: “A heat treatable TiB₂/Al-3.5Cu-1.5Mg-1Si composite fabricated by selective laser melting: microstructure, heat treatment and mechanical properties”, Composites Part B: Engineering 147 (2018) 162-168.

P. Wang, L. Deng, K.G. Prashanth, S. Pauly, J. Eckert, S. Scudino: “Microstructure and mechanical properties of Al-Cu alloys fabricated by selective laser melting of powder mixtures”, Journal of Alloys and Compounds 735 (2018) 2263-2266.

P. Wang, C. Gammer, F. Brenne, K.G. Prashanth, R.G. Mendes, M.H. Rümmeli, T. Gemming, J. Eckert, S. Scudino: “Microstructure and mechanical properties of a heat-treatable Al-3.5Cu-1.5Mg-1Si alloy produced by selective laser melting”, Materials Science and Engineering A 711 (2018) 562-570.

S. Pauly, P. Wang, U. Kühn, K. Kosiba, Experimental determination of cooling rates in selectively laser-melted eutectic Al-33Cu, Additive manufacturing, 22 (2018) 753-757

P. Wang, H.C. Li, K.G. Prashanth, J. Eckert, S. Scudino: “Selective laser melting of Al-Zn-Mg-Cu: Heat treatment, microstructure and mechanical properties”, Journal of Alloys and Compounds 707 (2017) 287-290.

K.G. Prashanth, S. Scudino, T. Maity, J. Das, J. Eckert: “Is the energy density a reliable parameter for materials synthesis by selective laser melting?”, Materials Research Letters (2017) DOI: 10.1080/21663831.2017.1299808.

K.G. Prashanth, S. Scudino, J. Eckert: “Defining the tensile properties of Al-12Si parts produced by selective laser melting”, Acta Materialia 126 (2017) 25-35.

J. Suryawanshi, K.G. Prashanth, S. Scudino, J. Eckert, O. Prakash, U.Ramamurty: “Simultaneous enhancements of strength and toughness in an Al-12Si alloy synthesized using selective laser melting”, Acta Materialia 115 (2016) 285-294.

K.G. Prashanth, S. Scudino, A.K. Chaubey, L. Löber, P. Wang, H. Attar, F.P. Schimansky, F. Pyczak, J. Eckert: “Processing of Al-12Si-TNM composites by selective laser melting and evaluation of compressive and wear properties”, Journal of Materials Research 31 (2016) 55-65.

P. Ma, Y. Jia, K.G. Prashanth, S. Scudino, Z. Yu, J. Eckert: “Microstructure and phase formation in Al-20Si-5Fe-3Cu-1Mg synthesized by selective laser melting”, Journal of Alloys and Compounds 657 (2016) 430-435.

K.G. Prashanth, H. Shakur Shahabi, H. Attar, V.C. Srivastava, N. Ellendt, V. Uhlenwinkel, J. Eckert, S. Scudino: “Production of high strength Al₈₅Nd₈Ni₅Co₂ alloy by selective laser melting”, Additive Manufacturing 6 (2015) 1-5.

K.G. Prashanth, S. Scudino, H.J. Klauss, K.B. Surreddi, L. Löber, Z. Wang, A.K. Chaubey, U. Kühn, J. Eckert, Microstructure and mechanical properties of AlSi12 produced by selective laser melting: Effect of heat treatment, Materials Science and Engineering: A, 590 (2014) 153-160

K.G. Prashanth, B. Debalina, Z. Wang, P.F. Gostin, A. Gebert, M. Calin, U. Kühn, M. Kamaraj, S. Scudino, J. Eckert: “Tribological and corrosion properties of Al-12Si produced by selective laser melting”, Journal of Materials Research 29 (2014) 2044-2054.