Spark plasma sintering of WC, cemented carbide and functional graded materials

Using PNC-60 powder with the addition of graphite, cylindrical products characterized by different compositions of core and outer layers were made. Some compacts were sintered via the conventional process, while others were subjected to the spark plasma sintering method (SPS) at different times and temperatures. The gradient microstructure was obtained in the transition zone by mixing powders during die filling, followed by pressing and diffusion during sintering. The effect of sintering parameters on the nature of the gradient zone and the morphology of the pores was shown. After conventional sintering, the gradient zone was wider than it was after SPS. Via SPS, the short sintering time confined the diffusion to a local range, making its influence on the gradient structure negligible. Differences in the microstructure were confirmed by functional description.

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Tribological Characterization of Micron-/Nano-Sized WC-9%Co Cemented Carbides Prepared by Spark Plasma Sintering at Elevated Temperatures

Materials ◽

10.3390/ma12060920 ◽

2019 ◽

Vol 12 (6) ◽

pp. 920 ◽

Cited By ~ 5

Author(s):

Saleh Wohaibi ◽

Abdul Mohammed ◽

Tahar Laoui ◽

Abbas Hakeem ◽

Akeem Adesina ◽

...

Keyword(s):

Wear Resistance ◽

Spark Plasma Sintering ◽

Room Temperature ◽

Elevated Temperatures ◽

Normal Load ◽

Cemented Carbide ◽

Plasma Sintering ◽

Dry Conditions ◽

Spark Plasma ◽

Track Area

The present study investigates the high temperature tribological performance of spark plasma sintered, nano- and micron-sized tungsten carbide (WC) bonded by 9 wt.% cobalt (Co). The composites were fabricated using a two-step procedure of mixing followed by spark plasma sintering (SPS). Ball-on-disc wear tests were conducted at a normal load of 30 N, linear speed of 0.1 m/s under dry conditions and at three different temperatures (room temperature, 300 °C and 600 °C). Field emission scanning electron microscopy (FESEM), optical profilometry and energy dispersive X-ray (EDS) spectroscopy were used to analyze the surface morphology and the wear track area. At room temperature, it was observed that the nano-sized WC composites exhibited better wear resistance than the micron-sized WC composites. The wear resistance of the nano-sized samples declined significantly relative to that of the micron-sized samples with an increase in temperature. This decline in performance was attributed to the higher surface area of nano-sized WC particles, which underwent rapid oxidation at elevated temperatures, resulting in poor wear resistance. The wear rate observed at 600 °C for the micron-sized WC composites was 75% lower than that of the nano-sized cemented carbide. Oxidative wear was observed to be the predominant wear mechanism for both cemented carbide samples at elevated temperatures.

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Preparation of Mg-W Graded Materials by Spark Plasma Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1869 ◽

2008 ◽

Vol 368-372 ◽

pp. 1869-1871

Author(s):

Qiang Shen ◽

Ying Hu Liu ◽

Jing Zhou ◽

Guo Qiang Luo ◽

Lian Meng Zhang

Keyword(s):

Spark Plasma Sintering ◽

Low Temperatures ◽

Functionally Graded ◽

Front Face ◽

Density Range ◽

Graded Materials ◽

Compression Waves ◽

Plasma Sintering ◽

Mass Fractions ◽

Spark Plasma

A new kind of functionally graded materials (FGM) with density gradient has come to show great potentials as flier-plates for creating quasi-isotropic compression waves. In order to meet the demand of lower density in the front face and wider density range for such flier-plate, Mg with a density of 1.74g/cm3 and W of 19.3g/cm3 are selected to make Mg-W system density graded materials. Mg-W alloys with various mass fractions of Mg and W were sintered by spark plasma sintering (SPS) technique at low temperatures, and the processing of densification is mainly investigated. It is found that, up to 92wt%W, the Mg-W alloys can be fully densified at 873K due to the conglutination of Mg particles. The Mg-W alloys still exist as a mechanical mixture of Mg and W. Finally, the Mg-W density graded materials with a density change from 1.74g/cm3 to 10.55g/cm3 have been successfully prepared.

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Sintering Behavior of Fly ash/NiCr Functionally Graded Materials Prepared by Spark Plasma Sintering (SPS)

Journal of the Japan Society of Powder and Powder Metallurgy ◽

10.2497/jjspm.57.333 ◽

2010 ◽

Vol 57 (5) ◽

pp. 333-337 ◽

Cited By ~ 1

Author(s):

Mamoru Daio ◽

Kazuhiro Hasezaki ◽

Ryuichi Shinoda ◽

Takahito Oikawa ◽

Ichiro Yoshioka

Keyword(s):

Fly Ash ◽

Spark Plasma Sintering ◽

Functionally Graded Materials ◽

Functionally Graded ◽

Sintering Behavior ◽

Graded Materials ◽

Plasma Sintering ◽

Spark Plasma

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Preparation of Functionally Graded Cu/AlN/Cu Electrode Materials for Thermoelectric Devices

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.2613 ◽

2007 ◽

Vol 336-338 ◽

pp. 2613-2615 ◽

Cited By ~ 1

Author(s):

Huai Quan Zhang ◽

Jing Feng Li

Keyword(s):

Spark Plasma Sintering ◽

Functionally Graded Materials ◽

Electrode Materials ◽

Functionally Graded ◽

Thermoelectric Devices ◽

Graded Materials ◽

Step Process ◽

Plasma Sintering ◽

Spark Plasma

The Cu/AlN/Cu functionally graded materials (FGMs) were successfully fabricated using the spark plasma sintering (SPS) method, and a two-step process was used. First, a symmetrical porositygraded AlN plate was prepared using AlN powder consisting of particles of varying sizes. Afterwards, graded Cu/AlN/Cu samples were made by introducing Cu into the pores of the external, porous AlN layer.

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Functionally Graded Nano Hardmetal Materials Made by Spark Plasma Sintering Technology

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.23.179 ◽

2005 ◽

Vol 23 ◽

pp. 179-182 ◽

Cited By ~ 4

Author(s):

Xinglong Tan ◽

Shaoyu Qiu ◽

Wenyan He ◽

Daifu Lei

Keyword(s):

Stainless Steel ◽

Internal Stress ◽

Spark Plasma Sintering ◽

Functionally Graded Materials ◽

Functionally Graded ◽

The Other ◽

Graded Materials ◽

Plasma Sintering ◽

Spark Plasma ◽

Sintering Processes

The properties of nano WC/Co hardmetals prepared by different Spark Plasma Sintering processes were measured. A 4-layer Functionally Graded Materials (FGM) was also obtained by Spark Plasma Sintering technology (SPS), starting from powders of nano WC/10%Co, nano WC/12%Co, micro WC/15%Co and stainless steel disk. The other 3-layer FGM was made from powders of nano 21%Al2O3/ZrO2, nickel and stainless steel. The SPS processing led to FGM free of internal stress, which was measured using Vickers indentations.

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