Oxygen-free Copper, whose English name is oxygen-free copper, refers to pure copper that contains no Oxygen and no residues of any deoxidizer. However, in actual production, due to process limitations, oxygen-free copper still contains very trace amounts of oxygen and some impurities. According to the standard regulations, the oxygen content of oxygen-free copper shall not exceed 0.003%, the total impurity content shall not exceed 0.05%, and the purity of copper shall be greater than 99.95%. According to the differences in oxygen content and impurity content, oxygen-free copper is further classified into No. 1 (C10100) and No. 2 (C10200) oxygen-free copper. The purity of oxygen-free copper No. 1 is as high as 99.97%, with the oxygen content and total impurity content not exceeding 0.003% and 0.03% respectively. The purity of oxygen-free copper No. 2 is 99.95%, and the oxygen content and total impurity content do not exceed 0.005% and 0.05% respectively.