Air Permeability of Maraging Steel Cellular Parts Made by Selective Laser Melting

Dhinakar, Annadurai; Li, Bai-En; Chang, Yo-Cheng; Chiu, Kuo-Chi; Chen, Jhewn‐Kuang

doi:10.3390/ma14113118

Cited by 6 publications

(4 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The gas permeability of the SLM cellular coupons is measured using apparatus [14] set up according to Darcy's Law or Equation (3) [28]. The inlet air pressure is kept constant at 20 psi (0.138 MPa or 1.36 atm) for permeability measurement.…”

Section: Porosity and Gas Permeability Measurementmentioning

confidence: 99%

See 1 more Smart Citation

Permeability of Additive Manufactured Cellular Structures—A Parametric Study on 17-4 PH Steels, Inconel 718, and Ti-6Al-4V Alloys

Liu

Cheng²,

Chiu³

et al. 2022

JMMP

Self Cite

View full text Add to dashboard Cite

Cellular structures of metallic alloys are often made for various industrial applications by additive manufacturing. The permeability for fluid flow in these cellular structures is important. The current investigated the gas fluidity of cellular structures made by selective laser melting (SLM). The porosity and permeability of the SLM cellular structures were measured for 17-4 PH stainless steel, Inconel 718, and Ti-6Al-4V alloys. The relations between porosity and energy density are expressed using the power law. The characteristic molar energies were 1.07 × 105, 9.02 × 104, and 7.11 × 104 J/mole for 17-4 PH steel, Ti-6Al-4V, and Inconel 718 alloys, respectively. 17-4 PH steel gave rise to higher porosity at the same energy density when compared with Ti-6Al-4V and Inconel 718 alloy. The values of these molar energy density are related to the heat needed to melt the alloys, viscosity, and thermal conductivity. It was further shown that air permeability is not only concerned with the percentage of porosity in the cellular materials, but it also relates to the tortuosity of pore pathways formed in the cellular materials. At the same porosity, Inconel 718 demonstrates higher air permeability in comparison with that of Ti-6Al-4V and 17-4 PH alloys due to its smoother pore pathways. Ti-6Al-4V, on the other hand, demonstrates the highest specific surface areas due to powder sticking along the pore pathways and led to the lowest permeability among the three alloys.

show abstract

Section: Porosity and Gas Permeability Measurementmentioning

confidence: 99%

“…Additive manufacturing by power bed fusion such as selective laser melting (SLM) is capable of building cellular structures by controlling energy density to form gas pathways among pores [14][15][16]. The microstructures and anisotropic properties of SLM parts are also greatly affected by printing parameters and energy density [17,18].…”

Section: Introductionmentioning

confidence: 99%

Permeability of Additive Manufactured Cellular Structures—A Parametric Study on 17-4 PH Steels, Inconel 718, and Ti-6Al-4V Alloys

Liu

Cheng²,

Chiu³

et al. 2022

JMMP

Self Cite

View full text Add to dashboard Cite

show abstract

“…The formation of reverse austenite is due to the matrix being enriched with elements that stabilise austenite [17], such as those resulting from the partial dissolution of Ni 3 (Ti, Mo) and the formation of Fe 2 Mo [18]. The surrounding matrix is enriched in Ni, which leads to partial reversion of the austenite [19]. Reverse austenite is remarkably stable and does not transform during cooling after ageing [20][21][22][23].…”

Section: Introductionmentioning

confidence: 99%

The Effect of Selective Laser Melting Fabrication Parameters on the Tensile Strength of an Aged New Maraging Steel Alloy with 8% Cr, Reduced Ni Content (7%), and No Co or Mo

Pérez-Gonzalo,

González-Pociño,

Alvarez-Antolin

et al. 2023

Materials

View full text Add to dashboard Cite

The aim of this paper was to optimise the manufacturing parameters of a new maraging steel alloy with 8% Cr, reduced Ni content (7%), and no Co or Mo. This alloy was developed by ArcelorMittal and its trade name is LeanSi. The alloy was produced using the selective laser melting (SLM) process. In the as-built state, the microstructure of the alloy was fully martensitic. The optimisation of the manufacturing parameters was determined via a multivariate factorial design of experiments including 12 experiments and three factors. The factors (i.e., the fabrication parameters) analysed were laser power, scanning speed, and hatch distance. The objective was to eliminate porosity and maximise density. It was concluded that, to achieve this, the laser power should be set at 250 W, the scanning speed at 1000 mm/s, and the hatch distance at 80 microns. The porosity obtained under these manufacturing parameters was 0.06 ± 0.03% with a confidence level of 95%. If these manufacturing parameters were modified, the material exhibited a defective interlayer bond with the formation of “balling” and high porosity. The tensile specimens tested in the as-built state showed plastic deformation. However, all the aged specimens showed brittle fracture behaviour, evidenced by the presence of very small micro-cavities (where the fracture energy consumed was very small) and small cleavage planes. The specimens produced with the manufacturing parameters at their optimum levels and aged at 480 °C for 2 h achieved tensile strength values that averaged 1430 MPa. The porosity of these specimens was reduced by more than 85%. Reverse austenite was detected at ageing temperatures of 540 °C upwards.

show abstract

“…The work by Davar Ali et al [27] demonstrates that by designing different gyroid and rectangular-pore lattices, it is possible to tailor permeability. A study from S. Ma et al [28] shows that SLM is an efficient technology to fabricate 316L steel lattice structures with the desired permeability and mechanical properties, while A. Dhinakar et al's [29] work shows that SLM processing parameters significantly influence the permeability of the fabricated lattice structures, as the processing parameters dictate these structures' dimensional and geometrical accuracy. A widespread industrial solution for injection mold gas venting is the use of commercially available porous inserts, commonly sintered metals, that are assembled in the molding system.…”

Section: Introductionmentioning

confidence: 99%

18Ni300 Maraging Steel Lattice Structures Fabricated via Laser Powder Bed Fusion—Mechanical Behavior and Gas Permeability

Oliveira,

Vieira,

Duarte

et al. 2023

Metals

View full text Add to dashboard Cite

Maraging steels have attracted the attention of the injection molding industry, mainly due to their mechanical properties. However, the use of these steels for complex inserts is still a challenge, given the limitations of conventional subtractive technologies. In this context, additive manufacturing technologies, especially Laser powder bed fusion (LPBF), arise as a solution for the manufacture of maraging steel parts with innovative designs. In this study, 18Ni300 maraging steel lattice structures with different architectures were designed and manufactured via Selective Laser Melting (SLM), targeting mold vents for gas escape during injection molding. Three types of structures, simple cubic (SC), body-centered cubic (BCC), and gyroid (G), with different dimensions were produced, and their mechanical performance under compression (prior and after aging treatment) and gas permeability were investigated. The produced structures displayed a first maximum compressive strength from 54.3 to 251.5 MPa and an absorbed energy (up to 0.5 strain) between 34.8 and 300.6 MJ/m3. After aging, these properties increased, with the first maximum compressive strength ranging from 93.0 to 453.3 MPa and the absorbed energy ranging from 34.8 to 300.6 MJ/m3. The SC structures’ permeability was found to be between 4.9 × 10−11 and 2.0 × 10−10 m2, while for the BCC structures, it was between 2.2 × 10−11 and 1.2 × 10−10 m2. The gyroid structures’ permeability ranged from 6.7 × 10−11 to 1.6 × 10−10 m2. This study shows that a tailored permeability can be attained through the design of AM lattice structures, via different architectures, that assure distinct mechanical properties.

show abstract

Air Permeability of Maraging Steel Cellular Parts Made by Selective Laser Melting

Cited by 6 publications

References 34 publications

Permeability of Additive Manufactured Cellular Structures—A Parametric Study on 17-4 PH Steels, Inconel 718, and Ti-6Al-4V Alloys

Permeability of Additive Manufactured Cellular Structures—A Parametric Study on 17-4 PH Steels, Inconel 718, and Ti-6Al-4V Alloys

The Effect of Selective Laser Melting Fabrication Parameters on the Tensile Strength of an Aged New Maraging Steel Alloy with 8% Cr, Reduced Ni Content (7%), and No Co or Mo

18Ni300 Maraging Steel Lattice Structures Fabricated via Laser Powder Bed Fusion—Mechanical Behavior and Gas Permeability

Contact Info

Product

Resources

About