Peculiarities of the neck growth process during initial stage of spark-plasma, microwave and conventional sintering of WC spheres

2012 ◽  
Vol 523 ◽  
pp. 1-10 ◽  
Author(s):  
Dmytro Demirskyi ◽  
Hanna Borodianska ◽  
Dinesh Agrawal ◽  
Andrey Ragulya ◽  
Yoshio Sakka ◽  
...  
Keyword(s):  
Growth Process ◽  
Neck Growth ◽  
Initial Stage ◽  
Conventional Sintering ◽  
Spark Plasma ◽  
Plasma Microwave

Neck growth kinetics during ultrasonic-assisted sintering of copper powder

2020 ◽  
Vol 234 (11) ◽  
pp. 2178-2188 ◽  
Author(s):  
Gurminder Singh ◽  
Pulak M Pandey
Keyword(s):  
Growth Kinetics ◽  
Copper Powder ◽  
Local Heating ◽  
Soaking Time ◽  
Neck Growth ◽  
Copper Particles ◽  
Initial Stage ◽  
Conventional Sintering ◽  
Ultrasonic Assisted ◽  
Vibration Assistance

The present paper presents an investigation of the neck growth kinetics during ultrasonic-assisted sintering of the loose spherical copper particles. The study was performed to identify the sintering mechanism during the initial stage sintering of the copper powder. The classical sphere-to-sphere approach was used to determine the neck growth between the particles at four different sintering temperatures 700, 800, 900 and 950 ℃ at different soaking time of 60, 180, 300, 600, and 900 s. The neck growth exponent was found to be 6.21, 4.92, 5.26 and 5.13 for different sintering temperatures, respectively, which signified the involvement of surface and volume diffusion mechanism during the initial stage sintering of copper particles with ultrasonic vibration assistance. The neck growth calculation was attempted to compare with conventional sintering. The evidence of the local heating between the particles was evolved from the activation energy calculations, which was found to be lower than the conventional sintering. An attempt was made to develop a numerical model for the prediction of neck growth by considering the rise in temperature due to friction between the particles owing to ultrasonic vibrations at different sintering temperature and soaking time. The model was obtained to be in-line with the trend of the experimental results.

scholarly journals Processing of MMC through conventional sintering and spark plasma sintering process: A review

2020 ◽  
Vol 988 ◽  
pp. 012092
Author(s):  
B Stalin ◽  
M Ravichandran ◽  
M Balasubramanian ◽  
C Anand Chairman ◽  
D Pritima ◽  
...  
Keyword(s):  
Spark Plasma Sintering ◽  
Sintering Process ◽  
Plasma Sintering ◽  
Conventional Sintering ◽  
Spark Plasma

Preparation and Magnetic Properties of Dense NiCuZn Ferrite by Spark Plasma Sintering

2008 ◽  
Vol 368-372 ◽  
pp. 601-603
Author(s):  
Xi Wei Qi ◽  
Ji Zhou ◽  
Zhen Xing Yue ◽  
Ming Ya Li ◽  
Xiu Mei Han
Keyword(s):  
Spark Plasma Sintering ◽  
Annealing Temperature ◽  
Annealing Treatment ◽  
Impurity Phase ◽  
Uniaxial Pressure ◽  
Plasma Sintering ◽  
Average Grain Size ◽  
Conventional Sintering ◽  
Spark Plasma ◽  
Nicuzn Ferrite

Dense NiCuZn ferrites consisting of fine grains were prepared by spark plasma sintering (SPS) at 750°C for 3 min under a uniaxial pressure of 15 MPa. The powders were densified to >95% of theoretical density by the SPS process, and the average grain size of the prepared NiCuZn ferrite was < 1 /m. The saturation magnetization of prepared specimens (without further annealing treatment) was approximate 50.54 emu/g, which was slightly smaller than that of 52.21 emu/g for specimens prepared by conventional sintering at 980°C for 4 h. Phase identifications indicated that prepared NiCuZn ferrite existed impurity phase (Cu2O), and Cu2O would gradually transform to CuO when annealing temperature increased.

The Growth Process of the PEO Films under Escalating Voltage Waveform

2011 ◽  
Vol 239-242 ◽  
pp. 720-723
Author(s):  
Li Wang ◽  
Wen Fu ◽  
Li Chen
Keyword(s):  
Corrosion Resistance ◽  
Growth Process ◽  
Ceramic Coatings ◽  
Voltage Waveform ◽  
Potentiodynamic Polarization Curves ◽  
Initial Stage ◽  
Electrolytic Oxidation ◽  
Superior Corrosion Resistance ◽  
Plasma Electrolytic ◽  
Peo Coatings

In order to get a clear picture for describing the growth process of plasma electrolytic oxidation coatings under escalating voltage waveform, the characteristics of PEO coatings formed at different reaction stages were systemically investigated. The morphology and corrosion resistance of the films were studied by scanning electron microscope and potentiodynamic polarization curves. The uniform, semi-transparent and better corrosion resistance of the oxide films on the magnesium electrode surface were formed owe to the extended anodizing time at the initial stage under escalating voltage mode. After sparking occurred, generated ceramic coatings were brokedown, melted, cooled and solidified continuously, so the ceramic coatings were uniform and dense. It also exhibited superior corrosion resistance.

scholarly journals Porosity and Microstructure Iron-Based Graded Materials Sintered by Spark Plasma Sintering and the Conventional Method

Metals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 264
Author(s):  
Krzysztof Zarębski ◽  
Piotr Putyra ◽  
Dariusz Mierzwiński
Keyword(s):  
Spark Plasma Sintering ◽  
Graded Materials ◽  
Gradient Zone ◽  
Die Filling ◽  
Plasma Sintering ◽  
Gradient Microstructure ◽  
Conventional Sintering ◽  
Spark Plasma ◽  
Local Range ◽  
Sintering Method

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.

Sign in / Sign up

Export Citation Format

Share Document