Cooling rate evaluation during solidification in the suction casting process

Kozieł, Tomasz; Pajor, Krzysztof; Gondek, Ł.

doi:10.1016/j.jmrt.2020.09.082

Cited by 20 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…SC requires 3-4 orders of magnitude lower feedstock material mass compared to PBF-LB, allowing resource-efficient pre-screening of melting-resolidification behavior. It is known that SC has far higher cooling rates (up to 10 2 K/s, depending on the apparatus parameters like critical section thickness as well as material properties) [36] than conventional casting. But the heat gradients and cooling rates of 10 6 -10 7 K/s [37] , as well as the solidification rates (e.g.…”

Section: Methodsmentioning

confidence: 99%

Upscaled laser synthesis of copper nanoparticles in acetone to correlate the surface modification of Nd-Fe-B feedstock properties with part properties after full melting and rapid solidification

Gabriel

Liu

Staab

et al. 2023

Preprint

View full text Add to dashboard Cite

The possibilities of nanoadditivation to achieve finer, more equiaxed grains unlock huge potential for the application field of functional materials, e.g. Nd-Fe-B magnets, where the control of the microstructure and the composition is of significant importance. The surface modification of hard magnetic microparticles by non-magnetic nanoparticles (NPs) opens a novel field of research. Here, especially Cu NPs with low amounts of oxides are of high relevance as colloidal nano-additive material. To increase the productivity of surfactant-free, laser-generated Cu NPs, we performed a process parameter study via laser ablation in acetone aiming for the highest possible productivity, increasing the throughput of NP additivation on the surface of functional feedstock micro powders. By optimizing the process parameters of laser power, laser fluence, repetition rate, volume flow, and spot size, a productivity of 0.19 µg/J of Cu NPs in acetone was achieved. Then we investigated how a fine microstructure of the magnet powder MQP-S can be retained to some extent along the process chain, throughout the melting and resolidification process during suction casting. A loading series of Cu NP nanoadditivation on magnet micro powders of 0.1, 0.5, 1.0, and 2.5 wt.% was analyzed regarding magnetic properties and microstructure of the as-built part. Using full melting conditions of MQP-S by producing samples via suction casting modified with different amounts of Cu NP additions leads to finer grains, but increasing α-Fe content. Overall, the results enable higher production rates of Cu NPs in acetone and provide insights into the influence of NP-supporting characteristics on the properties of permanent magnet micro powders after full melting and resolidification.

show abstract

Section: Methodsmentioning

confidence: 99%

Upscaled laser synthesis of copper nanoparticles in acetone to correlate the surface modification of Nd-Fe-B feedstock properties with part properties after full melting and rapid solidification

Gabriel

Liu

Staab

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

“…The ingots were thrice remelted under a Tigettered argon atmosphere to obtain composition homogeneity, and then suction cast into copper molds ( 3 -10 mm). The water cooling system temperature was set to 17 ± 1 °C [4].…”

Section: A Materialsmentioning

confidence: 99%

“…Furthermore, improving their glass forming ability (GFA) has also been an important aspect in their development. The first metallic glasses required high cooling rates (about 10 4 ÷10 6 K/s) to attain amorphous ribbons with thicknesses of only a dozen micrometers [4]. Understanding the thermodynamic and kinetic factors allowed to synthesize metallic glasses in bulk form, having at least 1 mm in diameter [5,6].…”

Section: Introductionmentioning

confidence: 99%

The Scavenging Effect of Different Rare-Earth Elements in the Low-Purity Zr50Cu40Al10 Alloy

Pajor

Rutkowski

Gondek

et al. 2022

Metall Mater Trans A

Self Cite

View full text Add to dashboard Cite

Glass forming alloys are very sensitive to oxygen contaminations. Here, the oxygen scavenging effect of five rare-earth elements (RREs) was studied when added to the Zr50Cu40Al10 alloy, synthesized from commercially available zirconium. The effects of precise REEs additions (Y, Sc, Lu, Gd, Nd) with respect to the measured oxygen content, based on the stoichiometric relationship in the M2O3 oxide are reported. Additionally, the influence of double and triple RRE-to-oxygen ratios on the critical diameter (Dc) and other glass forming ability (GFA) indicators were investigated. To evaluate the GFA and phase transformations during heating, differential thermal analysis was performed along with neutron diffraction. The combination of these two techniques allowed to identify crystallization products and distinguish the differences in phase transformations of low and high oxygen-content alloys. Microstructural analysis was carried out by means of electron microscopy (SEM, STEM), supported by X-ray diffraction. The best oxygen scavengers were found to be rare-earths that form cubic sesquioxides, i.e. Y, Sc and Lu, allowing to increase Dc in the high oxygen Zr50Cu40Al10 alloy from 2.5 mm up to 8 mm (double stoichiometric concentration of Y-to-oxygen). Our results indicate that low purity alloys can be easily vitrified, highlighting their potential for wide commercialization.

show abstract

“…3a, b). Although suction casting is regarded as a rapid solidification process, with cooling rates in the range of 10-10 3 K s −1 [42,43], microsegregation is seen in the interdendritic regions and the grain boundaries of the as-cast TNZT sample (Fig. 3b).…”

Section: Phase Constitution and Microstructural Characterizationmentioning

confidence: 99%

Microstructure and properties of TiB2-reinforced Ti–35Nb–7Zr–5Ta processed by laser-powder bed fusion

Batalha

Pinotti

Alnoaimy

et al. 2021

Journal of Materials Research

View full text Add to dashboard Cite

The Ti–35Nb–7Zr–5Ta (wt%, TNZT) alloy was reinforced with TiB2 and synthesized by L-PBF. The relatively small TiB2 particles change the solidification structure from cellular to columnar-dendritic and lead to submicron TiB precipitation in the β matrix. This results in pronounced grain refinement and reduction of texture. However, the microstructure of the additively manufactured TNZT-TiB2 is still different from the as-cast, unreinforced TNZT, which contains equiaxed and randomly oriented grains. The β phase is less stable in the as-cast samples, leading to stress-induced martensitic transformation and recoverable strain of 1.5%. The TNZT with 1 wt% of TiB2 presents significantly higher compressive strength (σYS = 495 MPa) compared to unreinforced samples (σYS = 430 MPa), without sacrificing ductility or altering Young’s modulus (E ≈ 46 GPa). The addition of a small fraction of TiB2 to the TNZT alloy synthesized by L-PBF is a promising alternative for manufacturing sophisticated components for biomedical applications. Graphical abstract

show abstract

Cooling rate evaluation during solidification in the suction casting process

Cited by 20 publications

References 12 publications

Upscaled laser synthesis of copper nanoparticles in acetone to correlate the surface modification of Nd-Fe-B feedstock properties with part properties after full melting and rapid solidification

Upscaled laser synthesis of copper nanoparticles in acetone to correlate the surface modification of Nd-Fe-B feedstock properties with part properties after full melting and rapid solidification

The Scavenging Effect of Different Rare-Earth Elements in the Low-Purity Zr50Cu40Al10 Alloy

Microstructure and properties of TiB2-reinforced Ti–35Nb–7Zr–5Ta processed by laser-powder bed fusion

Contact Info

Product

Resources

About