Microstructural design in LaCe misch-metal substituted 2:14:1-type sintered magnets by dual-alloy method

Severe plastic deformation (SPD) has received enormous interest over the last two decades as a method capable of producing fully dense and bulk ultra-fine grained (UFG) and nanocrystalline (NC) materials. Significant grain refinement obtained by SPD leads to improvement of mechanical, microstructural and physical properties. Compared to classical deformation processes, the big advantage of SPD manufacturing techniques, represented in particular by equal channel angular pressing (ECAP) is the lack of shape-change deformation and the consequent possibility to impart extremely large strain. In ECAP processing, the workpiece is pressed through a die in which two channels of equal cross-section intersect at an angle of ϕ and an additional angle of ψ define the arc of curvature at the outer point of intersection of the two channels. As a result of pressing, the sample theoretically deforms by simple shear and retains the same cross-sectional area to allow repeated pressings for several cycles. A commercial AlMgSi alloy was investigated in our study. The specimens were processed at room temperature for multiple passes, using three different ECAP dies. All samples (ECAP processed and as-received) were subjected to metallographic analysis and mechanical testing. Several correlations between the main processing parameters and the resulting microstructural aspect and mechanical features for the processed material were established. It was shown that severe plastic deformation by means of ECAP processing can be used in aluminum alloys microstructural design as an advanced tool for grain refinement in order to attain the desired microstructure and mechanical properties.

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Towards the Digitalisation of Porous Energy Materials: Evolution of Digital Approaches for Microstructural Design

Energy & Environmental Science ◽

10.1039/d1ee00398d ◽

2021 ◽

Author(s):

Zhiqiang Niu ◽

Valerie Pinfield ◽

Billy Wu ◽

Huizhi Wang ◽

Kui Jiao ◽

...

Keyword(s):

Energy Materials ◽

Energy Devices ◽

Essential Components ◽

Microstructural Design

Porous energy materials are essential components of many energy devices and systems, the development of which have been long plagued by two main challenges. The first is the ‘curse of...

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Progress and perspectives in dielectric energy storage ceramics

Journal of Advanced Ceramics ◽

10.1007/s40145-021-0500-3 ◽

2021 ◽

Vol 10 (4) ◽

pp. 675-703

Author(s):

Dongxu Li ◽

Xiaojun Zeng ◽

Zhipeng Li ◽

Zong-Yang Shen ◽

Hua Hao ◽

...

Keyword(s):

Energy Storage ◽

Power Systems ◽

Temperature Stability ◽

Pulse Power ◽

Research Progress ◽

High Temperature Stability ◽

Dielectric Ceramic ◽

Microstructural Design ◽

Pulse Power Systems ◽

Fatigue Endurance

AbstractDielectric ceramic capacitors, with the advantages of high power density, fast charge-discharge capability, excellent fatigue endurance, and good high temperature stability, have been acknowledged to be promising candidates for solid-state pulse power systems. This review investigates the energy storage performances of linear dielectric, relaxor ferroelectric, and antiferroelectric from the viewpoint of chemical modification, macro/microstructural design, and electrical property optimization. Research progress of ceramic bulks and films for Pb-based and/or Pb-free systems is summarized. Finally, we propose the perspectives on the development of energy storage ceramics for pulse power capacitors in the future.

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