The effect of temperature on the physical and mechanical properties of nanostructured boron nitride by spark plasma sintering

Ceramic matrix composites (CMCs) based on silicon carbide (SiC) are promising materials for applications as structural components used under high irradiation flux and high temperature conditions. The addition of SiC fibers (SiCf) may improve both the physical and mechanical properties of CMCs and lead to an increase in their tolerance to failure. This work describes the fabrication and characterization of novel preceramic paper-derived SiCf/SiCp composites fabricated by spark plasma sintering (SPS). The sintering temperature and pressure were 2100 °C and 20–60 MPa, respectively. The content of fibers in the composites was approx. 10 wt.%. The matrix densification and fiber distribution were examined by X-ray computed tomography and scanning electron microscopy. Short processing time avoided the destruction of SiC fibers during SPS. The flexural strength of the fabricated SiCf/SiCp composites at room temperature varies between 300 and 430 MPa depending on the processing parameters and microstructure of the fabricated composites. A quasi-ductile fracture behavior of the fabricated composites was observed.

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Defined an Optimized Molding for Physical and Mechanical Properties of W–Cu Nanocomposite Through Spark Plasma Sintering Using Gene Expression Programming: The Combination of Artificial Intelligence and Material Science

SN Computer Science ◽

10.1007/s42979-021-00901-4 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Mohammdreza Shojaei ◽

Gholam Reza Khayati

Keyword(s):

Gene Expression ◽

Artificial Intelligence ◽

Mechanical Properties ◽

Spark Plasma Sintering ◽

Material Science ◽

Gene Expression Programming ◽

Physical And Mechanical Properties ◽

Plasma Sintering ◽

Spark Plasma

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Spark Plasma Sintering and Characterization of Mixed h-BN Powders with Different Grain Sizes

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.281.414 ◽

2018 ◽

Vol 281 ◽

pp. 414-419

Author(s):

Feng Rui Zhai ◽

Min Lu ◽

Ke Shan ◽

Zhong Zhou Yi ◽

Zhi Peng Xie

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Boron Nitride ◽

Spark Plasma Sintering ◽

Hexagonal Boron Nitride ◽

Orientation Degree ◽

Plasma Sintering ◽

Spark Plasma ◽

Crystallization Degree

Mixtures of two grades of hexagonal boron nitride (h-BN) powder differing in their grain size and crystallinity were spark plasma sintering in a vacuum. The influences of the mixing ratio of h-BN powders on the densification, microstructure and mechanical properties were investigated in detail. The results show that the smaller grain size, the lower crystallization degree and the higher density and mechanical properties. While the orientation degree of flake h-BN grains can be greatly enhanced by using h-BN powder with larger particle size. As the increasing of nanometer h-BN powder adding amount, the relative density has the same “V” shape changing trends with mechanical properties. In addition, the orientation of boron nitride grains varied widely, and a nearly isotropic material was prepared from a mixture containing 90wt.% nanometer powder.

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X-ray diffraction layer-by-layer analysis of tungsten carbide-based hard alloys

Industrial laboratory Diagnostics of materials ◽

10.26896/1028-6861-2020-86-8-38-42 ◽

2020 ◽

Vol 86 (8) ◽

pp. 38-42

Author(s):

K. E. Smetanina ◽

P. V. Andreev ◽

E. A. Lantsev ◽

M. M. Vostokov ◽

N. V. Malekhonova

Keyword(s):

Mechanical Properties ◽

Phase Composition ◽

Spark Plasma Sintering ◽

Physical And Mechanical Properties ◽

Hard Alloys ◽

Layer By Layer ◽

X Ray ◽

Novel Technologies ◽

Plasma Sintering ◽

Spark Plasma

Improvement of the physical and mechanical properties of hard alloys based on WC – Co widely used in manufacturing of structural and tool products nowadays results from the use of novel technologies providing formation of a homogeneous high-density structures. Slight deviations of the carbon content from the equilibrium state lead to the formation of brittle η-phases (in particular, Co3W3C) and, accordingly, to deterioration of the mechanical properties of the product. We present the results of studying the homogeneity of the phase composition of the samples of hard alloys WC + 10% Co, obtained using advanced technologies of plasma-chemical synthesis and spark plasma sintering (SPS). The layer-by-layer X-ray phase analysis revealed the heterogeneity of the phase composition in depth: the brittle η-phase (Co3W3C) appears at a depth of ≥100 μm and reaches a constant value of 18 ± 1 wt.% at >200 μm, which indirectly confirms the hypothesis of carbon diffusion from graphite punches contacting with the surface of sintered samples and makes it possible to expand the range of parameters affecting the process of spark plasma sintering.

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