Ultra-Fine Treatment of SiC Powder and Its Effect on Microstructure and Properties of SiC Ceramic

The ultra-fine treatment of industrial SiC powder was carried out by fluidized bed opposed jet milling (QLM-100K), and the influences of grinding parameters on the ultra-fine treatment were studied. A better grinding result is achieved through a higher crushing pressure and a higher sorter frequency and the ultra-fine treated SiC powder possesses a smaller particle size, a narrower particle-size distribution, a higher specific surface area and reduced agglomeration. The effects of ultra-fine treatment on the compaction behaviors, sintering behaviors, properties and microstructure of SiC ceramics were investigated. The compact with ultra-fine treated powder has a higher density and a lower sintering temperature. The densification and mechanical properties of the ceramics can be ameliorated obviously and the microstructure defects of the ceramics decrease.

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Particle size distribution control and related properties improvements of tungsten powders by fluidized bed jet milling

Advanced Powder Technology ◽

10.1016/j.apt.2017.04.002 ◽

2017 ◽

Vol 28 (6) ◽

pp. 1603-1610 ◽

Cited By ~ 15

Author(s):

Rui Li ◽

Mingli Qin ◽

Chengcheng Liu ◽

Zheng Chen ◽

Xuanli Wang ◽

...

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Fluidized Bed ◽

Jet Milling ◽

Tungsten Powders

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Influence and Mechanism Analysis of Particle Size Distribution of Multi-System Mineral Admixture on Concrete Performance

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1036.386 ◽

2021 ◽

Vol 1036 ◽

pp. 386-394

Author(s):

Fu Xing Cheng ◽

Yong Liu ◽

Ji Xiao ◽

Xiao Xu Deng ◽

Hai Long Wang

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Particle Size Distribution ◽

Specific Surface ◽

Mechanical Activation ◽

Size Distribution ◽

Surface Area ◽

Specific Surface Area ◽

Mineral Admixture ◽

Mechanism Analysis

To explore the effect of mechanical activation on the particle size distribution of the composite admixture a self-designed test jet mill is used. We have studied the effects of different specific surface areas of composite admixtures on the workability, mechanical properties and durability of concrete and combined X-ray diffraction (XRD) with scanning electron microscopy (SEM) to analyze the mechanism of concrete performance improvement. Results showed that, mechanical activation can significantly increase the content of particles below 3 um; appropriate increase in the specific surface area of composite admixture is conducive to improving the performance of concrete; As the specific surface area increases, the hydration activity of the composite admixture increases first and then tends to be stable; during the hydration process, more thin-plate Ca(OH)2 is converted into needle-shaped AFt, which improves the cement-based material and thereby improving the macro mechanical properties and durability.

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Structural and mechanical properties of cBN composites by regulating particle size distribution and holding time

International Journal of Refractory Metals and Hard Materials ◽

10.1016/j.ijrmhm.2021.105635 ◽

2021 ◽

pp. 105635

Author(s):

Huanli Ji ◽

Zhihong Li ◽

Min Liu

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Holding Time

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Effect of Particle Size Distribution on Laser Powder Bed Fusion Manufacturability of Copper

BHM Berg- und Hüttenmännische Monatshefte ◽

10.1007/s00501-021-01107-0 ◽

2021 ◽

Author(s):

Massimiliano Bonesso ◽

Pietro Rebesan ◽

Claudio Gennari ◽

Simone Mancin ◽

Razvan Dima ◽

...

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Physical And Mechanical Properties ◽

Powder Bed Fusion ◽

Laser Powder Bed Fusion ◽

Powder Bed ◽

Cooling Channels ◽

Scan Speed

AbstractOne of the major benefits of the Laser Powder Bed Fusion (LPBF) technology is the possibility of fabrication of complex geometries and features in only one-step of production. In the case of heat exchangers in particular, this is very convenient for the fabrication of conformal cooling channels which can improve the performance of the heat transfer capability. Yet, obtaining dense copper parts printed via LPBF presents two major problems: the high reflectivity of 1 μm (the wavelength of commonly used laser sources) and the high thermal conductivity of copper that limits the maximum local temperature that can be attained. This leads to the formation of porous parts.In this contribution, the influence of the particle size distribution of the powder on the physical and mechanical properties of parts produced via LPBF is studied. Three copper powders lots with different particle size distributions are used in this study. The effect on densification from two laser scan parameters (scan speed and hatching distance) and the influence of contours scans on the lateral surface roughness is reported. Subsequently, samples manufactured with the optimal process parameters are tested for thermal and mechanical properties evaluation.

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