Effect of Pulse Current on the Microstructure of Tungsten Electrode in Tensile Process

Abstract:

The forming of rare earth tungsten electrode is difficult. The mechanical properties and microstructure evolution of several φ2.4mm rare earth tungsten electrodes were studied by SEM, EBSD and TEM technology. The static tensile test was carried out in different pulse current density, and the temperature of the samples in processing was measured with K thermocouple. The results showed that the sample had the best elongation of 8.87% when the pulse current density was 800 A/mm². SEM analysis showed that the second phase was broken and some of them were spheroidized in electric sample. It is indicated that the electric pulse accelerated the formation of [110] texture and the low angle boundaries decreased by EBSD, and TEM analysis revealed that the dislocation cell wall was thinner and the adjacent cell got merged in electric sample.

• Periodical: Materials Science Forum (Volume 817)
• Pages: 104-108
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.817.104
• Online since: April 2015
• Authors: Jie Cao, Jian Can Yang*, Wen Guang Zhu
• Keywords: Boundaries, Dislocation Cell, Elongation, Texture, Tungsten Electrode

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