The processing technology of copper rods mainly includes several steps: smelting, casting, rolling, annealing, and finishing.
1. Smelting: The selected copper raw materials are smelted. Smelting is usually carried out in a high-temperature furnace, with a temperature generally around 1200℃. During the smelting process, impurities in the copper need to be removed to improve its purity. After smelting, the molten copper is poured into a mold and allowed to cool and solidify.
2. Casting: Casting involves pouring the molten copper into a pre-made mold, which cools to form a preliminary copper billet. Casting methods include sand casting and metal casting; choosing the appropriate casting method can result in better casting quality.
3. Rolling: After casting, the copper billet needs to be rolled. Rolling is the process of pressing the copper billet into shape at high temperatures using mechanical equipment. Through rolling, the diameter and length of the copper rod can be adjusted to the required specifications, and its mechanical properties can be improved. Rolling is divided into hot rolling and cold rolling. Hot rolling is suitable for mass production, while cold rolling is suitable for products with high precision requirements.
4. Annealing: Rolled copper rods often exhibit internal stress, and annealing is a crucial step in eliminating this stress. The annealing process involves heating the copper rod to a specific temperature and then slowly cooling it to improve its plasticity and toughness while reducing its hardness.
5. Finishing: After the above processes, the copper rod typically requires finishing. Finishing includes cutting, grinding, and polishing to achieve higher dimensional accuracy and surface finish. This step is essential for ensuring the final performance of the copper rod.