按***用途分，有油桶用板、搪瓷用板、弹板用板等；按表面涂镀层分，有镀锌薄板、镀锡薄板、镀铅薄板、塑料复合钢板等。

According to professional use, there are oil  board, enamel plate, bulletproof plate and so on. According to surface coating, there are galvanized sheet, tin plate, leaded sheet, plastic  steel plate and so on.

合金元素与铁、碳的相互作用

合金元素加入钢中后，主要以三种形式存在钢中。即：与铁形成固溶体；与碳形成碳化物；在高合金钢中还可能形成金属间化合物。

The interaction of alloying elements with iron and carbon

When alloy elements are added to steel, they mainly exist in three forms. Namely: to form a solid solution with iron; carbide and carbon; in high alloy steels are also likely to form intermetallic compounds.

装饰材料分为两大部分：一部分为室外材料，一部分为室内材料。室内材料再分为石材，板材、片材、型材、线材五个类型。

Decorative materials are divided into two parts: one is outdoor materials, the other is indoor materials. Indoor materials are further divided into five types: stone, sheet, sheet, profile and wire.

有的胶合板是将两个不同纹路的单板贴在一起制成的，所以在选择上要注意夹板拼缝处应严密，没有高低不平现象。挑选胶合板时，应注意挑选不散胶的胶合板。如果手敲胶合板各部位时，声音发脆，则证明质量良好，若声音发闷，则表示胶合板已出现散胶现象。

Some plywood plywood is made of two different lines of the single board together, so in the choice of the splints should be careful to pay attention to the joint, there is no uneven phenomenon. When choosing plywood, you should pay attention to selecting plywood without glue. If the hand knocks on the plywood parts, the sound is crisp, which proves that the quality is good. If the voice is stuffy, it means that the plywood has already appeared loose glue phenomenon.