Magnetic Properties of Al‐doped B₄C and SiC Ceramics

Abstract

Al-doped B 4 C and Al-doped SiC ceramic compounds were synthesized by high-temperature solid-state sintering. Ferromagnetic (FM) ordering was observed in the doped semiconducting ceramics. The changes in the FM ordering with doping level were different in the two doped systems although they were prepared by similar experimental condition. Our results indicated that some of the C in B 4 C were replaced by the Al atoms, and these displaced C atoms existed in the form of graphite. The synthesized SiC samples, undoped or Al doped, were found to be a mixture consisting of the magnetic and nonmagnetic SiC polytypes. The mechanisms in the generation of the FM ordering due to the dopants in the two ceramics followed different routes.A. Bandyopadhyay-contributing editor Manuscript No. 33091.

Sintering and optical quality of highly transparent yb‐doped yttrium lanthanum oxide ceramics

“…All of them are heterovalent and vastly reduce laser efficiency when the ceramics is used as a host to rare-earth ions. Recent investigations reveals a potential of La 2 O 3 to serve as an isovalent aid to sinter both undoped [6] and doped with ether Yb 3+ [7] or Nd 3+ [8] yttria ceramics. This paper deals with fabrication and investigation of highly transparent Yb-doped yttrium lanthanum oxide ceramics.…”

Simultaneous Operando Characterization of Crystallographic and Electrochemical Properties of Ni-Ce0.9Gd0.1O2-δSolid Oxide Fuel Cell Anode

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Electrical and magnetic properties of silicon carbide composites with titanium and niobium carbide as sintering aids

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