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When purchasing wires, we should not only look at the brand, model, appearance, size and price, but also the material. Only products with qualified materials will not affect the later use. What are the materials of wires? How to buy wires? Let's follow Xiaobian and have a look!

What are the materials of wires

There are 5 kinds of wire materials, which are conductor materials: copper, aluminum, silver, gold, etc; Insulation materials: PE, NR, chloroprene rubber, nitrile rubber, cable paper, paint; Sheath material: polyethylene, nylon, etc; Semiconductive materials: silicon, germanium, etc; Barrier materials: copper wire, copper strip, aluminum strip, etc.

How to buy wires:

1. Packing

We should pay attention to the packaging when purchasing, because the packaging is easy to be damaged during production and transportation. In addition, a certificate of conformity shall be provided in the package, and the specification, size, length, date, name and address of the product shall be indicated on the certificate.

2. View manufacturing process

At the time of purchase, a section of product can be randomly cut to see whether the internal core is in the middle of the insulation layer. If it is not in the middle, it indicates that the process is not qualified and the core is biased. In addition, you can bend the thread head repeatedly by hand to check whether the product is soft by hand and whether the compression resistance is good.

3. Check wire size

When purchasing, it is necessary to see whether the length and thickness of the product are qualified, because it is stipulated in the industry that the length error cannot be greater than 2% and the cross-sectional wire diameter cannot be greater than 0.02%.

4. See the thickness and color

During purchase, one section of the three wires can be cut off and peeled. If the material is unqualified, the copper wire will be dark or oxidized, and the thickness of the wire will also be different. If the material is qualified, the copper wire will show metallic luster and the plastic skin will be bright.