As an important engineering material, nodular cast iron is widely used in each department of national economy.

作为一种重要的工程材料，球墨铸铁广泛应用于国民经济各部门。

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As an important engineering material, nodular cast iron is widely used in each department of national economy.

作为一种重要的工程材料，球墨铸铁广泛应用于国民经济各部门。

youdao