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A new simulation method for cathode spot crater formation and development in vacuum arc with CuCr nanocrystalline alloy electrode

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Journal of Physics D: Applied Physics
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Lijun Wang
Lijun Wang
Lijun Wang
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Cong Wang
Cong Wang
Cong Wang
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Xinyi Liu
Xinyi Liu
Xinyi Liu
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Runming Zhang
Runming Zhang
Runming Zhang
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Abstract and Figures

In order to further understand the formation and development process of cathode spot crater on copper-chromium (CuCr) nanocrystalline alloy electrode in vacuum arc, a new simulation method considering the distribution of different components is proposed. And a two-dimensional axisymmetric model is established to study the effects of different components on the formation and development of cathode spot crater. The differences in physical properties are considered in the model, and the interface between the Cu component and the Cr component is effectively tracked. The distribution, flow, and heat transfer of the Cu and Cr components are simulated. To directly demonstrate the advantages of the method, the simulation results are compared with those adopting the method that linearly combines the physical property parameters according to the weight percentage of components. Simulation result shows that the presence of Cr components has an important influence on the formation and development of cathode spot crater on CuCr nanocrystalline alloy electrode. The effects of different weight percentages of Cr components on the formation and development of cathode spot crater on CuCr nanocrystalline alloys are also studied. The results indicate that with the improvement of Cr component weight percentages, the temperature on the cathode spot crater is increased, and the fluidity of liquid metal is reduced during erosion. Finally, the simulation results have been compared with experimental results of other researchers.
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Journal of Physics D: Applied Physics
J. Phys. D: Appl. Phys. 58 (2025) 175202 (11pp) https://doi.org/10.1088/1361-6463/adbfa5
A new simulation method for cathode
spot crater formation and development
in vacuum arc with CuCr nanocrystalline
alloy electrode
Lijun Wang∗, Cong Wang, Xinyi Liu, Runming Zhang and Yiduo Xie
State Key Laboratory of Electrical Insulation and Power Equipment, Xi’an Jiaotong University, Xi’an
710049, People’s Republic of China
E-mail: lijunwang@mail.xjtu.edu.cn
Received 18 November 2024, revised 8 March 2025
Accepted for publication 12 March 2025
Published 20 March 2025
Abstract
In order to further understand the formation and development process of cathode spot crater on
copper-chromium (CuCr) nanocrystalline alloy electrode in vacuum arc, a new simulation
method considering the distribution of different components is proposed. And a
two-dimensional axisymmetric model is established to study the effects of different components
on the formation and development of cathode spot crater. The differences in physical properties
are considered in the model, and the interface between the Cu component and the Cr component
is effectively tracked. The distribution, ow, and heat transfer of the Cu and Cr components are
simulated. To directly demonstrate the advantages of the method, the simulation results are
compared with those adopting the method that linearly combines the physical property
parameters according to the weight percentage of components. Simulation result shows that the
presence of Cr components has an important inuence on the formation and development of
cathode spot crater on CuCr nanocrystalline alloy electrode. The effects of different weight
percentages of Cr components on the formation and development of cathode spot crater on
CuCr nanocrystalline alloys are also studied. The results indicate that with the improvement of
Cr component weight percentages, the temperature on the cathode spot crater is increased, and
the uidity of liquid metal is reduced during erosion. Finally, the simulation results have been
compared with experimental results of other researchers.
Keywords: CuCr nanocrystalline alloy, cathode spot crater, vacuum arc, liquid metal, simulation
1. Introduction
Copper-chromium (CuCr) alloy is widely used as contact
material in vacuum circuit breakers [1,2]. Cr metal has high
melting and boiling points, and exhibits excellent erosion
resistance. Cu metal has good electrical conductivity, but
its erosion resistance is relatively poor due to its low melt-
ing point. CuCr alloy combines the advantages of these two
elements. While ensuring good conductivity, it signicantly
∗Author to whom any correspondence should be addressed.
improves the material’s erosion resistance. Therefore, CuCr
alloy has been widely used in vacuum circuit breakers and has
become an ideal contact material.
In order to evaluate the anti-erosion performance of CuCr
contact materials and better understand the erosion process
and behavior of CuCr alloy in vacuum, researchers have been
committed to characterizing the morphology and state of the
contact after erosion. Feng et al [3] observed the morpho-
logy of cathode spot crater of nanocrystalline and microcrys-
talline CuCr25 alloy by scanning electron microscope (SEM).
Zhang et al [4] examined the microstructure of CuCr50 alloy
1
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