Sintering Kinetics of the Powder during Fields-Activated Micro-Forming and Sintering (Micro-FAST) of Copper Micro-Gears

Abstract:

Forming of micro-components from powder with fields-activated sintering technology (FAST) renders different forming and sintering mechanisms, comparing to that occurring during the forming of macro-sized components with a similar technology. Establishing a good understanding of these mechanisms would help process design and control aiming at achieving desired quality of the components to be formed. This paper presents a study and the results on the sintering kinetics of the powder during Micro-FAST for the fabrication of micro-gears (the module is 0.2 and the pitch diameter 1.6 mm) from copper powder. The results showed that the densification of copper powder is related largely to the bulk plastic-deformations of the particles and the melting of the particles at contact interfaces. Particularly, it is revealed that plastic deformations of the copper particles mainly occurred at approximately 340 °C and melting of the particle-interfaces at approximately 640 °C. Differently, in a densification process with a traditional powder sintering method, grain growth and neck growth would, normally, be two dominant mechanisms that achieve the densification of powder.

• Periodical: Key Engineering Materials (Volumes 622-623)
• Pages: 854-860
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.622-623.854
• Online since: September 2014
• Authors: Kun Lan Huang*, Yi Yang, Yi Qin
• Keywords: Field-Activated Sintering Technology (FAST), Micro-Forming, Sintering Kinetics

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