Copper plate has good electrical conductivity, thermal conductivity, corrosion resistance and processing properties, and can be welded and brazed. It contains less impurities that reduce electrical conductivity and thermal conductivity, and a small amount of oxygen has little effect on electrical conductivity, thermal conductivity and processing properties, but it is easy to cause "hydrogen disease", and it is not suitable for processing (annealing, annealing, welding, etc.) and use.