Brass is an alloy of copper and zinc.

黄铜是铜锌合金。

《牛津词典》

He knew brass is an alloy of copper and zinc.

他知道了黄铜是铜和锌的合金。

youdao

Brass (Brass) : Brass is an alloy of copper and zinc, general zinc content in the 30 to 40%, the color of the Brass between with the increase of the content of zinc from dark red.

黄铜(Brass)：黄铜是铜和锌的合金，一般锌含量在30 ~ 40%之间，黄铜的颜色随锌含量的增加从暗红色。

youdao

Many French horns, for example, are made of nickel silver, an alloy of copper, zinc, and nickel (it's silver in name and color only), and some are made of nickel bronze, an alloy of copper, tin, and nickel. (Brass itself is an alloy of copper and zinc.) Many brass instruments are silver-plated (sterling silver on brass), and some are gold-plated.

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