Ultrafast reaction‐sintering of grain size‐controlled titanium niobate from TiO 2 and Nb 2 O 5

Magnesium aluminate (MA) spinel is synthesized by reaction sintering from alumina and magnesia. The effects of mechanical activation of Al2O3 on reaction sintering were investigated. Non-milled a - Al2O3 and a - Al2O3 high-energy ball milled for 12h, 24h and 36h were mixed with a MgO analytical reagent according to the stoichiometric MA ratio, respectively and pressed into billets with diameters of 20mm and height of 15mm. The green-body billets were then sintered at high temperature in an air atmosphere. The results show that bulk density, relative content of MA and grain size of MA increase with increasing high-energy ball milling time of Al2O3. However prolonged milling time over 24h has a small beneficial effect on the densification of MA. Bulk density and grain size of a sample of a- Al2O3 milled for 24h are 3.30g/cm3 and 4-5 mm, respectively.

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Impact of grain size on the optoelectronic performance of 2D Ruddlesden–Popper perovskite-based photodetectors

Journal of Materials Chemistry C ◽

10.1039/d0tc04350h ◽

2021 ◽

Vol 9 (1) ◽

pp. 110-116

Author(s):

Bohee Hwang ◽

Youngjun Park ◽

Jang-Sik Lee

Keyword(s):

Grain Size ◽

High Performance ◽

Solvent Engineering ◽

Size Controlled

This paper presents the synthesis of grain size-controlled 2D perovskite films for high-performance photodetectors by combining solvent engineering and hot casting.

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Reaction Sintering of Transparent Aluminum Oxynitride (AlON) Ceramics Using MgO and Y2O3 as Co-Additives

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.697.7 ◽

2016 ◽

Vol 697 ◽

pp. 7-11 ◽

Cited By ~ 3

Author(s):

Shen Qi ◽

Xiao Jian Mao ◽

Bao Yan Chai ◽

Long Zhang

Keyword(s):

Grain Size ◽

Optical Properties ◽

Liquid Phase ◽

Aluminum Nitride ◽

Sintering Temperature ◽

Direct Reaction ◽

Reaction Sintering ◽

Aluminum Oxynitride ◽

Sintering Additives

Transparent aluminum oxynitride (AlON) ceramics have been prepared through a method based on direct reaction sintering of alumina and aluminum nitride powders using MgO and Y2O3 as co-additives. The sintering additives could cause the formation of liquid phase during sintering, which would greatly promote the densification and eliminate pores. The grain size of AlON is about 50-100μm. The influence of different component of Al2O3 and AlN as well as sintering temperature on microstructure and optical properties of AlON have been studied. High transparent AlON ceramics with the in-line transmittance of 80.3% at 2000 nm wavelength have been prepared when the concentration of sintering additives was 0.16wt% Y2O3 and 0.02wt% MgO.

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