DC Arc Plasma Treatment for Defect Reduction in WC-Co Granulated Powder
Abstract
:1. Introduction
2. Materials and Methods
3. Results
3.1. Powder Morphology
3.2. Compression Test for the WC-Co Powders
3.3. Crystalline Structure
4. Discussion
4.1. Identification of Co Peaks
4.2. Processing Behavior of Plasma-Treated Powder Particles
4.3. Availability of Plasma-Treated Powder as Raw Material for Additive Manufacturing Technology
5. Conclusions
- (1)
- We succeeded in obtaining a low-defect powder of high sphericity with minimal decarburization.
- (2)
- Porosity reduction was found to proceed by filling of gaps among WCs by molten cobalt.
- (3)
- Concerns regarding the vaporization of cobalt and changes in WC–Co compositional ratios during high-temperature plasma treatment were found to be unwarranted, as defects in WC–Co were effectively reduced without significant change in the WC–Co chemical compositional ratio under the applied treatment conditions.
Author Contributions
Funding
Conflicts of Interest
References
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Powder | Flow-Ability (s/50 g) | Apparent Density (g/cm3) |
---|---|---|
Raw powder | 17.8 | 7.6 |
Treated powder | 11.3 | 11.0 |
Powder | A (m) | St (MPa) |
---|---|---|
Raw powder | 12.9 ± 0.9 | 280 ± 92 |
Treated powder | 13.1 ± 0.3 | 1340 ± 123 |
Powder | a (Å) | c (Å) | c/a |
---|---|---|---|
Raw powder | 2.9028 | 2.8349 | 0.977 |
Treated powder | 2.9054 | 2.8366 | 0.976 |
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Itagaki, H.; Yachi, T.; Ogiso, H.; Sato, H.; Yamashita, Y.; Yasuoka, J.; Funada, Y. DC Arc Plasma Treatment for Defect Reduction in WC-Co Granulated Powder. Metals 2020, 10, 975. https://doi.org/10.3390/met10070975
Itagaki H, Yachi T, Ogiso H, Sato H, Yamashita Y, Yasuoka J, Funada Y. DC Arc Plasma Treatment for Defect Reduction in WC-Co Granulated Powder. Metals. 2020; 10(7):975. https://doi.org/10.3390/met10070975
Chicago/Turabian StyleItagaki, Hirotomo, Taisei Yachi, Hisato Ogiso, Harumichi Sato, Yorihiro Yamashita, Junichi Yasuoka, and Yoshinori Funada. 2020. "DC Arc Plasma Treatment for Defect Reduction in WC-Co Granulated Powder" Metals 10, no. 7: 975. https://doi.org/10.3390/met10070975