Grain growth in uranium nitride prepared by spark plasma sintering

The shortage of dysprosium as an alloying element has directed the research on the grain size refining of NdFeB, since higher coercivities can be obtained by decreasing the grain size, without Dy addition. The Spark Plasma Sintering (SPS) is a consolidation process which allows densification at lower temperatures and shorter dwell times of sintering, thus avoiding the grain growth. Therefore, the typical temperature of sintering of NdFeB magnets can be decreased from 1050°C to around 800°C, as it was evidenced by means of SPS shrinkage curves and the high densified microestructure obtained in this work.

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Inhibition of grain growth in liquid-phase sintered SiC ceramics by AlN additive and spark plasma sintering

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2010.04.006 ◽

2010 ◽

Vol 30 (10) ◽

pp. 2117-2122 ◽

Cited By ~ 34

Author(s):

Mikinori Hotta ◽

Junichi Hojo

Keyword(s):

Liquid Phase ◽

Grain Growth ◽

Spark Plasma Sintering ◽

Sic Ceramics ◽

Plasma Sintering ◽

Spark Plasma

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The Effect of Sintering Temperature on Microstructure and Properties of 94wt% WC - 3wt% TiC - 6wt% Co Sintered by Spark Plasma Sintering

10.21203/rs.3.rs-832398/v1 ◽

2021 ◽

Author(s):

Vahid Aghaali ◽

Touradj Ebadzadeh ◽

Seyed Mohammad Zahraee ◽

Seyed Mohammad Mirkazemi

Keyword(s):

Fracture Surface ◽

Tungsten Carbide ◽

Grain Growth ◽

Spark Plasma Sintering ◽

Apparent Density ◽

Sintering Temperature ◽

Total Density ◽

Microstructure And Properties ◽

Plasma Sintering ◽

Spark Plasma

Abstract Cemented carbide 94wt% WC − 3wt% TiC − 6wt% Co was sintered by spark plasma sintering at various temperatures of 1200, 1300, and 1400°C and the effect of sintering temperature on the microstructure and properties of this type of hard metals, such as total density, apparent density, hardness, and fracture surface were measured and observed using Field Emission-Scanning Electron Microscopy(FE-SEM), Optical Microscopy (OM), X-ray diffractometry (XRD) and mechanical test instruments. The results showed that the apparent density of the samples increased with increasing sintering temperature from 1200℃ to1300℃ from 13.98 g/cm3 to 14.23 g/cm3, respectively. But in the case of sample sintered at 1400℃, the density was reduced to 14.20 g/cm3. Also, micro-hardness results showed that the hardness of sintered samples increased with the increase of sintering temperature. For the sample sintered at 1200°C the hardness value of 1746.41HV was obtained which increased with increasing sintering temperature from 1300℃ to 1400℃ from 2094.33HV to 2280.97HV, respectively. At the optimum sintering temperature, it was found that TiC inhibited the grain growth of tungsten carbide and increased the hardness values. In addition, as expected, the grain growth of tungsten carbide increased with increasing sintering temperatures. Examination of the fracture surface of sintered samples at different temperatures also showed that brittle fracture involves fracture.

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