Grain growth stagnation in the dense nanocrystalline yttria prepared by combustion reaction and quick pressing with an ultra-high heating rate

The technique of combustion reaction and quick pressing was adopted to prepare dense nanocrystalline ceramics. The densification process of magnesia compact with a particle size of 100 nm was investigated, under the applied pressure of up to 170 MPa, and the temperature of 1740–2080 K with ultra-high heating rate of above 1700 K/min. As a result, pure magnesia ceramics with a relative density of 98.8% and an average grain size of 120 nm was obtained at 1740 K and 170 MPa, while the ones with decreased relative density and increased grain size were produced under the increasing temperature and the identical pressure conditions. The results indicated that grain growth of the nanocrystalline magnesia was effectively restrained by the combined effect of the ultra-high heating rate and the high pressure. Moreover, under the particular sintering conditions, there existed an appropriate temperature range for the preparation of dense nanocrystalline magnesia, and the excessive temperature would not only exaggerate grain growth but also impede densification.

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Microstructural evolution and mechanism of grain growth in magnesia ceramics prepared by high pressure and temperature with ultra-high heating rate

Science China Technological Sciences ◽

10.1007/s11431-014-5518-0 ◽

2014 ◽

Vol 57 (6) ◽

pp. 1085-1092 ◽

Cited By ~ 6

Author(s):

JiangHao Liu ◽

ZhengYi Fu ◽

WeiMin Wang ◽

JinYong Zhang ◽

Hao Wang ◽

...

Keyword(s):

High Pressure ◽

Heating Rate ◽

Grain Growth ◽

Microstructural Evolution ◽

High Heating Rate ◽

High Pressure And Temperature ◽

High Heating

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Investigations on High Heating Rate and Precision Calibration of the Thermoelectric Characteristics of the Tool and Work Materials

CIRP Annals ◽

10.1016/s0007-8506(07)63359-9 ◽

1983 ◽

Vol 32 (1) ◽

pp. 47-51 ◽

Cited By ~ 3

Author(s):

H.J. Xu ◽

X.C. Tong ◽

X.S. Zhao ◽

Y.Z. Zhang ◽

J. Peklenik

Keyword(s):

Heating Rate ◽

High Heating Rate ◽

High Heating

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Metal oxide nanoparticles formed from solution droplets under high heating rate

Experimental Thermal and Fluid Science ◽

10.1016/j.expthermflusci.2012.03.029 ◽

2012 ◽

Vol 43 ◽

pp. 23-31 ◽

Cited By ~ 1

Author(s):

Francesco Carbone ◽

Alberto C. Barone ◽

Federico Beretta ◽

Andrea D’Anna

Keyword(s):

Metal Oxide ◽

Heating Rate ◽

Metal Oxide Nanoparticles ◽

Oxide Nanoparticles ◽

High Heating Rate ◽

High Heating

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High heating rate sintering and microstructural evolution assessment using the discrete element method

Open Ceramics ◽

10.1016/j.oceram.2021.100182 ◽

2021 ◽

Vol 8 ◽

pp. 100182

Author(s):

Mirele Horsth Paiva Teixeira ◽

Vasyl Skorych ◽

Rolf Janssen ◽

Sergio Yesid Gómez González ◽

Agenor De Noni Jr ◽

...

Keyword(s):

Discrete Element Method ◽

Heating Rate ◽

Microstructural Evolution ◽

Discrete Element ◽

High Heating Rate ◽

High Heating ◽

Element Method

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Gasification of High Heating-rate Biomass-derived Chars at Elevated Temperatures

Energy Procedia ◽

10.1016/j.egypro.2017.03.369 ◽

2017 ◽

Vol 105 ◽

pp. 642-647

Author(s):

Tian Li ◽

Yanqing Niu ◽

Liang Wang ◽

Terese Løvås

Keyword(s):

Heating Rate ◽

Elevated Temperatures ◽

High Heating Rate ◽

High Heating

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XPS and Electron Microscopy Study of Oxide-Scale Evolution on Ignition Resistant Mg-3Ca Alloy at Low and High Heating Rates

Experimental Results ◽

10.1017/exp.2020.41 ◽

2020 ◽

Vol 1 ◽

Author(s):

L. A. Villegas-Armenta ◽

R. A. L. Drew ◽

M. O. Pekguleryuz

Keyword(s):

Oxide Scale ◽

Heating Rate ◽

Photoelectron Spectroscopy ◽

Microscopy Study ◽

Electron Microscopy Study ◽

High Heating Rate ◽

Heating Rates ◽

Oxide Interface ◽

Protective Oxide ◽

High Heating

AbstractEarlier work by the authors suggested that the formation of molten eutectic regions in Mg-Ca binary alloys caused a discrepancy in ignition temperature when different heating rates are used. This effect was observed for alloys where Ca content is greater than 1 wt%. In this work, the effect of two heating rates (25 °C/min and 45 °C/min) on the ignition resistance of Mg-3Ca is evaluated in terms of oxide growth using X-ray Photoelectron Spectroscopy. It is found that the molten eutectic regions develop a thin oxide scale of ~100 nm rich in Ca at either heating rate. The results prove that under the high heating rate, solid intermetallics are oxidized forming CaO nodules at the metal/oxide interface that eventually contribute to the formation of a thick and non-protective oxide scale in the liquid state.

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Effects of Heating Rate on Formation of Globular and Acicular Austenite during Reversion from Martensite

Metals ◽

10.3390/met9020266 ◽

2019 ◽

Vol 9 (2) ◽

pp. 266 ◽

Cited By ~ 3

Author(s):

Xianguang Zhang ◽

Goro Miyamoto ◽

Yuki Toji ◽

Tadashi Furuhara

Keyword(s):

Heating Rate ◽

High Temperatures ◽

The Other ◽

Growth Mode ◽

High Heating Rate ◽

Heating Rates ◽

Other Hand ◽

High Heating ◽

Martensite Matrix

The effects of heating rate on the formation of acicular and globular austenite during reversion from martensite in Fe–2Mn–1.5Si–0.3C alloy have been investigated. It was found that a low heating rate enhanced the formation of acicular austenite, while a high heating rate favored the formation of globular austenite. The growth of acicular γ was accompanied by the partitioning of Mn and Si, while the growth of globular γ was partitionless. DICTRA simulation revealed that there was a transition in growth mode from partitioning to partitionless for the globular austenite with an increase in temperature at high heating rate. High heating rates promoted a reversion that occurred at high temperatures, which made the partitionless growth of globular austenite occur more easily. On the other hand, the severer Mn enrichment into austenite at low heating rate caused Mn depletion in the martensite matrix, which decelerated the reversion kinetics in the later stage and suppressed the formation of globular austenite.

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