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Synthesis of Mg-based alloys with rare-earth element addition by means of mechanical alloying

Lesz Sabina, Hrapkowicz Bartłomiej, Gołombek Klaudiusz, Karolus Małgorzata, Janiak Patrycja

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 5

art. no. e137586

EN

Magnesium-based alloys are widely used in the construction, automotive, aviation and medical industries. There are many parameters that can be modified during their synthesis in order to obtain an alloy with the desired microstructure and advantageous properties. Modifications to the chemical composition and parameters of the synthesis process are of key importance. In this work, an Mg-based alloy with a rare-earth element addition was synthesized by means of mechanical alloying (MA). The aim of this work was to study the effect of milling times on the Mg-based alloy with a rare-earth addition on its structure and microhardness. A powder mixture of pure elements was milled in a SPEX 8000D high energy shaker ball mill under an argon atmosphere using a stainless steel container and balls. The sample was mechanically alloyed at the following milling times: 3, 5, 8 and 13 h, with 0.5 h interruptions. The microstructure and hardness of samples were investigated. The Mg-based powder alloy was examined by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and using a Vickers microhardness test. The results showed that microhardness of the sample milled for 13 h was higher than that of those with milling time of 3, 5 and 8 h.

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Microstructural Characterization of U-10wt.%Zr Fuel Slugs Containing Rare-Earth Elements Prepared by Modified Injection Casting

Lee Sang-Hun, Kim Ki-Hwan, Kuk Seoung-Woo, Park Jeong-Yong, Choi Ji-Hoon

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 3

953--957

EN

U-10wt.%Zr metallic fuel slugs containing rare-earth (RE: a rare-earth alloy comprising 53% Nd, 25% Ce, 16% Pr and 6% La) elements for a sodium-cooled fast reactor were fabricated by modified injection casting as an alternative method. The distribution, size and composition of the RE inclusions in the metallic fuel slugs were investigated according to the content of the RE inclusions. There were no observed casting defects, such as shrunk pipes, micro-shrinkage or hot tears formed during solidification, in the metallic fuel slugs fabricated by modified injection casting. Scanning electron micrographs and energy-dispersive X-ray spectroscopy (SEM-EDS) showed that the Zr and RE inclusions were uniformly distributed in the matrix and the composition of the RE inclusions was similar to that of a charged RE element. The content and the size of the RE inclusions increased slightly according to the charge content of the RE elements. RE inclusions in U-Zr alloys will have a positive effect on fuel performance due to their micro-size and high degree of distribution.

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Rare-Earth Elements Recovery on the Example of Europium (III) from Lean Technogenic Raw Materials

Lobacheva O., Dzhevaga N.

Journal of Ecological Engineering

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2017

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Vol. 18, nr 6

122--126

EN

Europium (III) recovery from nitrate solutions in a form of dodecyl sulfates using extraction methods was studied. Distribution and recovery coefficients as a function of equilibrium aqueous phase рН value were received. Conclusions on the effectiveness of presented method depending on the assigned task were drawn. The aims of this study were the development of rare-earth elements recovery and separation methods by using extraction with surfactant and distribution coefficients separation as well as recovery coefficient experimental validation with their subsequent introduction for poor mineral raw materials industrial processing. The authors study the rare-earth metals distribution and recovery coefficients during the extraction processes as a function of aqueous phase pH value with recovered compound form determination and thermodynamical justification.

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Uwagi o zawartości pierwiastków ziem rzadkich w wapieniach i dolomitach z okolic Krakowa

Vierek A.

Przegląd Geologiczny

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2005

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Vol. 53, nr 5

413--417

EN

Rare-earth elements (REE) were determined for the Upper Jurassic limestone and dolomites from the following outcrops: Góra OEw. Anny, Kostrze Quarry, Księża Góra, and Skały Twardowskiego. REE patterns are similar for all the investigated samples. Dolomites and limestone are enriched in light REE, they exhibit positive La anomalies, and negative Ce and Eu anomalies. Negative Ce and Eu anomalies are typical for oxidizing environments during dolomitization processes. Distinct enrichment in light REE comparing to heavy REE indi-cates that the sea water was not the only component of dolomitization fluids.