The uniaxial-compression creep behavior of semi-graphitic carbon products was investigated using modified Rapoport equipment in a K3AlF6–Na3AlF6–AlF3 and a Na3AlF6–AlF3 system. The stress exponent is low for the K3AlF6–Na3AlF6–AlF3 system in the steady-state creep stage. With an increase in graphitization degree and grain size, the interlayer space and porosity of the tested samples decrease after aluminum electrolysis. A low temperature can suppress carbon-cathode damage. Based on these stress exponents and a microstructural investigation using transmission electron microscopy, it is proposed that dislocation glide is the dominant creep mechanism for the carbon cathode during aluminum electrolysis in the steady-state creep stage.
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30 January 2018
The Acknowledgment at the end of the paper should read: Financial support from the National Natural Science Foundation of China (NSFC) (No. 170410656) and the Collaborative Innovation Center of Nonferrous Metals, Henan Province (15A450001) is gratefully acknowledged.
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Financial support from the Collaborative Innovation Center of Nonferrous Metals Henan Province (15A450001) is gratefully acknowledged.
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A correction to this article is available online at https://doi.org/10.1007/s11015-018-0582-5.
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Wang, W., Chen, W. & Gu, W. Creep Deformation of Carbon-Based Cathode Materials for Low-Temperature Aluminum Electrolysis. Metallurgist 61, 717–725 (2017). https://doi.org/10.1007/s11015-017-0555-0
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DOI: https://doi.org/10.1007/s11015-017-0555-0