Mechanical property and phase evolution of the hydrates of CAC-bonded alumina castables during drying at 110 °C

The paper examines the phase evolution in blends consisting of different proportions of stainless steel (SS316) and Al (0, 25, 65 and 85 wt. %) powders during high-energy ball milling by x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy. An attempt has also been made to study the mechanical property of the bulk samples obtained by hot pressing the ball milled powder blend at suitable a temperature and pressure. The results of microstructural changes and mechanical property and the ability of consolidation of the amorphous/nanocrystalline powders by high-pressure techniques to develop engineering components has been discussed and highlighted.

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A novel method to fabricate porous single phase O’-sialon ceramic and improve its mechanical property

Science of Sintering ◽

10.2298/sos2103387m ◽

2021 ◽

Vol 53 (3) ◽

pp. 387-395

Author(s):

Haiqiang Ma ◽

Chonggao Bao

Keyword(s):

Mechanical Property ◽

Pore Size ◽

Single Phase ◽

Bending Strength ◽

Phase Evolution ◽

Porous Ceramics ◽

Si3n4 Powder ◽

Novel Method ◽

Gas Pressure Sintering ◽

Sintering Method

Nowadays, the O?-sialon ceramics are synthesized by the reaction of Si3N4, SiO2 and Al2O3. However, it is difficult to achieve the single phase materials. Here, we have successfully developed porous single phase O?-sialon ceramics by pre-oxidation combined with gas-pressure sintering method. The effects of ?-Si3N4 powder on the microstructure, phase evolution, mechanical property were investigated. The result illustrated that the main crystal phase of the porous ceramics was composed of the single O?-sialon phase. The pores were well distributed and generated from the decomposition of Si2N2O. The elongated O?-sialon grains were found and formed around pore walls. Additionally, the addition of ?-Si3N4 powder was beneficial for improving the bending strength because of the reduction of porosity and pore size. The porous O?-sialon ceramics with uniform pores obtained the excellent bending strength when the ?-Si3N4 powder was 6 wt%.

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Thermomechanical Treatment of a 4340 Ni-Cr-Mo Alloy Steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100098083 ◽

1981 ◽

Vol 39 ◽

pp. 314-315 ◽

Cited By ~ 1

Author(s):

M.T. Jahn ◽

J.C. Yang ◽

C.M. Wan

Keyword(s):

Mechanical Property ◽

Chemical Composition ◽

Alloy Steel ◽

Thermomechanical Treatment ◽

Room Temperature ◽

Good Combination ◽

Thermal Treatments ◽

Low Carbon ◽

4340 Steel ◽

Good Improvement

4340 Ni-Cr-Mo alloy steel is widely used due to its good combination of strength and toughness. The mechanical property of 4340 steel can be improved by various thermal treatments. The influence of thermomechanical treatment (TMT) has been studied in a low carbon Ni-Cr-Mo steel having chemical composition closed to 4340 steel. TMT of 4340 steel is rarely examined up to now. In this study we obtain good improvement on the mechanical property of 4340 steel by TMT. The mechanism is explained in terms of TEM microstructures4340 (0.39C-1.81Ni-0.93Cr-0.26Mo) steel was austenitized at 950°C for 30 minutes. The TMTed specimen (T) was obtained by forging the specimen continuously as the temperature of the specimen was decreasing from 950°C to 600°C followed by oil quenching to room temperature. The thickness reduction ratio by forging is 40%. The conventional specimen (C) was obtained by quenching the specimen directly into room temperature oil after austenitized at 950°C for 30 minutes. All quenched specimens (T and C) were then tempered at 450, 500, 550, 600 or 650°C for four hours respectively.

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Effects of hydrogen charging and electrotransport treatment on the anodic polarization behavior and mechanical property of Alloy 600

Korean Journal of Metals and Materials ◽

10.3365/kjmm.2015.53.11.770 ◽

2015 ◽

Vol 53 (11) ◽

pp. 770-777

Author(s):

Jung-Gu Kim ◽

Jin-Seok Park ◽

Yong-Sang Kim ◽

Tae-Heum Nam

Keyword(s):

Mechanical Property ◽

Anodic Polarization ◽

Alloy 600 ◽

Hydrogen Charging ◽

Polarization Behavior

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Chemical Availability of Bromide Dictates CsPbBr3 Nanocrystal Growth

10.26434/chemrxiv.8081504 ◽

2019 ◽

Author(s):

Je-Ruei Wen ◽

Benjamin Roman ◽

Freddy Rodriguez Ortiz ◽

Noel Mireles Villegas ◽

Nicholas Porcellino ◽

...

Keyword(s):

Reaction Time ◽

Growth Mechanism ◽

Chemical Control ◽

Critical Role ◽

Phase Evolution ◽

Detailed Understanding ◽

Semiconductor Nanocrystal ◽

Nanocrystal Growth ◽

Chemical Availability

Lack of detailed understanding of the growth mechanism of CsPbBr3 nanocrystals has hindered sophisticated morphological and chemical control of this important emerging optoelectronic material. Here, we have elucidated the growth mechanism by slowing the reaction kinetics. When 1-bromohexane is used as an alternative halide source, bromide is slowly released into the reaction mixture, extending the reaction time from ~3 seconds to greater than 20 minutes. This enables us to monitor the phase evolution of products over the course of reaction, revealing that CsBr is the initial species formed, followed by Cs4PbBr6, and finally CsPbBr3. Further, formation of monodisperse CsBr nanocrystals is demonstrated in a bromide-deficient and lead-abundant solution. The CsBr can only be transformed into CsPbBr3 nanocubes if additional bromide is added. Our results indicate a fundamentally different growth mechanism for CsPbBr3 in comparison with more established semiconductor nanocrystal systems and reveal the critical role of the chemical availability of bromide for the growth reactions.<br>

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