青铜(bronze)

通常为铜和锡的合金。早在西元前3000年（参阅Bronze Age）就已制造出青铜，现仍广泛使用。约自西元前1000年起，在工具和武器中以铁代替青铜，这是因为铁较铜和锡丰富。青铜的熔点较低，较易铸造。青铜也较纯铁坚硬，也远比它耐腐蚀。钟铜的特性在於受敲击时能发出宏亮的声音，它是一种含锡量较高（20～25%）的青铜。雕塑青铜的含锡量不到10%，还加有锌和铅的混合物，从工艺上看是一种黄铜。磷青铜铸锭的含磷量少於1%，铸件只含微量，特别适用於作泵的柱塞、阀和套。在机械工业中也使用锰青铜，它含有少量锡或甚至不含锡，但含有大量锌和可达4.5%的锰。铝青铜含有高达16%的铝和少量其他金属如铁或镍，特别坚硬和耐腐蚀；可铸造或锻造成管件、泵、齿轮、船用螺旋桨和涡轮叶片。很多「铜币」实际上是用青铜铸造的，其典型成分是约4%的锡和1%的锌。

English version：

bronze

Alloy traditionally composed of copper and tin. Bronze was first made before 3000 BC (see Bronze Age) and is still widely used, though iron often replaced bronze in tools and weapons after about 1000 BC because of iron's abundance compared to copper and tin. Bronze is harder than copper, more readily melted, and easier to cast. It is also harder than iron and far more resistant to corrosion. Bell metal (which produces pleasing sounds when struck) is bronze with 20-25% tin content. Statuary bronze, with less than 10% tin and an admixture of zinc and lead, is technically a brass. The addition of less than 1% phosphorus improves the hardness and strength of bronze; that formulation is used for pump plungers, valves, and bushings. Also useful in mechanical engineering are manganese bronzes, with little or no tin but considerable amounts of zinc and up to 4.5% manganese. Aluminum bronzes, containing up to 16% aluminum and small amounts of other metals such as iron or nickel, are especially strong and corrosion-resistant; they are cast or wrought into pipe fittings, pumps, gears, ship propellers, and turbine blades. Most “copper” coins are actually bronze, typically with about 4% tin and 1% zinc.

参考文章

• 《青铜葵》读后感6篇600字读后感作文
• 《青铜葵》读后感8篇400、500字读后感作文
• 《青铜葵花》读后感4篇2000字读后感作文
• 《青铜葵》读后感6篇700字读后感作文
• 《青铜葵》读后感8篇500字读后感作文
• 青铜火鸡鸡
• 《青铜葵花》读后感6篇700字读后感作文
• 《青铜葵》读后感6篇800、900字读后感作文
• 《青铜葵》读后感8篇500、600字读后感作文
• 《青铜葵》读后感6篇800字读后感作文