夹克、套装、背心、领带仿佛是青铜材质，引人注目。

Bronze as a jacket, as a suit, as a waistcoat and as a tie.

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采用紫铜材质，具有较高的机械性能和抗热抗疲劳性能。

Use of copper material with high mechanical properties and thermal fatigue resistance.

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但是劣质铜，铜材质里面含有杂质，用手一弯就断成两截，里面可以看到有黑色杂质，这个是绝对不能采用的。

But the poor quality of copper, copper material which contains impurities, broken into two parts on hand curved, which can be seen in black impurities, this is definitely not used.

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