Excellent strength–ductility balance of Sc-Zr-modified Al–Mg alloy by tuning bimodal microstructure via hatch spacing in laser powder bed fusion

Ekubaru, Yusufu; Gokcekaya, Ozkan; Ishimoto, Takuya; Sato, Kazuhisa; Manabe, Koki; Wang, Pan; Nakano, Takayoshi

doi:10.1016/j.matdes.2022.110976

Cited by 46 publications

(18 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…26) From a microstructural perspective, the formation of a bimodal structure with fine equiaxed grains at the bottom of the molten pool and elongated grains extending toward the center of the molten pool is a common feature of aluminum alloys. 27,28) The existence of intermetallic compound particles inside the fine equiaxed particles suggests that they act as a nucleation site to generate randomly oriented equiaxed grains. The major axes of the elongated grains are oriented along the ©100ª direction (approximately opposite to the heat flow).…”

Section: Am For Light Metal Materials: Overviewmentioning

confidence: 99%

“…The major axes of the elongated grains are oriented along the ©100ª direction (approximately opposite to the heat flow). 28) Magnesium alloys are particularly reactive toward oxygen and nitrogen and pose a high risk of ignition and explosion. Therefore, there exist very few studies of manufacturing them with PBF using their powders as raw materials, when compared to titanium and aluminum alloys.…”

Section: Am For Light Metal Materials: Overviewmentioning

confidence: 99%

See 1 more Smart Citation

Review — Microstructural Control and Functional Enhancement of Light Metal Materials via Metal Additive Manufacturing

Ishimoto

Nakano

2023

Mater. Trans.

View full text Add to dashboard Cite

Additive manufacturing (AM) has been attracting a great deal of attention in both academia and industry in recent years as a technology that could bring innovation to manufacturing. AM was originally developed as a method specialized in fabricating three-dimensional structures by the additive manner. However, in reality, a huge number of parameters involved in AM has a significant effect on the microstructure and the resulting physicochemical properties of the metallic material. Therefore, in very recent years, metal AM is being recognized as a technology for controlling the microstructure of metals rather than its shape. In addition, AM can even customize the microstructure of each site by applying locally controlled heat energy. The ability to simultaneously control complex shapes and microstructures will add even higher value to lightweight metal materials. This paper describes the potential of metal AM to control material and shape properties that dictates the essential mechanical properties of the product with introducing latest results.

show abstract

Section: Am For Light Metal Materials: Overviewmentioning

confidence: 99%

Section: Am For Light Metal Materials: Overviewmentioning

confidence: 99%

Review — Microstructural Control and Functional Enhancement of Light Metal Materials via Metal Additive Manufacturing

Ishimoto

Nakano

2023

Mater. Trans.

View full text Add to dashboard Cite

show abstract

“…However, the suggestion of the mechanism relating to remelting seems to be still prevailing as described in a recent review on the progress of aluminum‐alloy LPBF [ 24 ] and in a review specifically on LPBF of Sc‐containing aluminum alloys. [ 25 ] Recently, Ekubaru et al [ 23 ] demonstrated that controlling hatch spacing can control the amount of equiaxed grains and thus can control the strength of the alloy through grain‐boundary strengthening. A recent effort on the alloy design for microstructure control in LPBF of aluminum alloys also was centered on the modification of the alloys using Sc.…”

Section: Introductionmentioning

confidence: 99%

“…Since Spierings et al's studies, there has continuously been a strong research effort on a number of aspects of LPBF of Al-Mg alloys containing various amounts of Sc and/or Zr. [11][12][13][14][15][16][17][18][19][20][21][22][23] Contents of Sc and Zr differ in various studies so that the kinetics of forming Al 3 (Sc,Zr) may differ. In Zhang et al's [11] study using P/v = 0.18 J mm À1 , Al 3 (Sc,Zr) particles up to 90 nm are found in the as-built state.…”

Section: Introductionmentioning

confidence: 99%

On the Mechanism of Formation of Bimodal Grain Structure in Al–4.5Mg–0.7Sc–0.3Zr Alloy Processed by Laser Powder Bed Fusion

Chernyshova¹,

Guraya

Martínez-Amesti

et al. 2023

Adv Eng Mater

View full text Add to dashboard Cite

Scalmalloy is an Al–Mg alloy with additions of Sc and Zr originally developed as a high‐strength aluminum alloy with σ0.2 ≥ 450 MPa for aerospace industry. It is now well understood that the alloy is amendable for processing by laser powder bed fusion (LPBF). However, the mechanism of formation of the equiaxed‐columnar bimodal grain structure during LPBF is not ascertained yet, fully. Herein, this gap is addressed with special focus on the distributions of critical elements such as Sc and various particles that form during LBPF. It is found that strong and weak segregation of Mg and Sc, respectively, occurs in the final solidification areas of the fine‐ and equiaxed‐grain regions. The coarser and columnar grain regions show weak segregation of Mg and no Sc segregation. A priori knowledge on the Al–Sc eutectic reaction, its dependence on cooling rates, and the well‐known thermal and solidification conditions related to the track location during LPBF is used to ascertain the mechanism of formation of the bimodal grain structure. The mechanism suggested is substantiated by the location‐dependent elemental distributions and the various particles that are observed.

show abstract

“…Therefore, they have been widely adopted in industrial fields, such as manufacturing automobiles, motorcycles, airplanes, and spacecraft [ 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. Al alloys with fine equiaxed grain microstructures exhibit excellent characteristics with respect to the aforesaid applications; therefore, inoculants are introduced as heterogeneous nucleation sites for further microstructure refinement [ 5 , 6 , 7 , 8 , 9 , 19 , 20 , 21 ]. However, the cost of the inoculants, which are rare earth elements, leads to a considerable increase in the price of the powder.…”

Section: Introductionmentioning

confidence: 99%

Effect of Rapid Heating and Cooling Conditions on Microstructure Formation in Powder Bed Fusion of Al-Si Hypoeutectic Alloy: A Phase-Field Study

2022

View full text Add to dashboard Cite

Al alloy parts fabricated by powder bed fusion (PBF) have attracted much attention because of the degrees of freedom in both shapes and mechanical properties. We previously reported that the Si regions in Al-Si alloy that remain after the rapid remelting process in PBF act as intrinsic heterogeneous nucleation sites during the subsequent resolidification. This suggests that the Si particles are crucial for a novel grain refinement strategy. To provide guidelines for grain refinement, the effects of solidification, remelting, and resolidification conditions on microstructures were investigated by multiphase-field simulation. We revealed that the resolidification microstructure is determined by the size and number of Si regions in the initial solidification microstructures and by the threshold size for the nucleation site, depending on the remelting and resolidification conditions. Furthermore, the most refined microstructure with the average grain size of 4.8 µm is predicted to be formed under conditions with a large temperature gradient of Gsol = 106 K/m in the initial solidification, a high heating rate of HR = 105 K/s in the remelting process, and a fast solidification rate of Rresol = 10−1 m/s in the resolidification process. Each of these conditions is necessary to be considered to control the microstructures of Al-Si alloys fabricated via PBF.

show abstract

Excellent strength–ductility balance of Sc-Zr-modified Al–Mg alloy by tuning bimodal microstructure via hatch spacing in laser powder bed fusion

Cited by 46 publications

References 52 publications

Review — Microstructural Control and Functional Enhancement of Light Metal Materials via Metal Additive Manufacturing

Review — Microstructural Control and Functional Enhancement of Light Metal Materials via Metal Additive Manufacturing

On the Mechanism of Formation of Bimodal Grain Structure in Al–4.5Mg–0.7Sc–0.3Zr Alloy Processed by Laser Powder Bed Fusion

Effect of Rapid Heating and Cooling Conditions on Microstructure Formation in Powder Bed Fusion of Al-Si Hypoeutectic Alloy: A Phase-Field Study

Contact Info

Product

Resources

About