n.碳化
动词char的现在分词形式.
The sodium silicate makes the cork stick to the mold surface and also helps to withstand the charring action of the molten lead alloy. 硅酸钠能使软木粉粘结在模具表面，而且还有助于软木粉耐受熔融铅合金的碳化作用。
