The insulating layer is pure natural rubber, copper wire for copper, so, in order to ensure the safety of wire and cable of good conductivity.

绝缘层一般为纯天然橡胶，铜丝为无氧铜，这样，才能保证线芯的良好导电性及电缆的安全性。

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This paper studied the effects of rare earth elements on the properties(such as hardness, electrical conductivity and resistance to corrosion)of pure copper used in touching wire of electric railway.

研究了稀土对电气铁路电车线用纯铜硬度、导电性、 耐磨性、耐蚀性的影响。结果表明，随稀土加入量的不同，上述性能都有一定程度的变化。

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