What the meanig of «Corrosion of Copper»?
Copper and its alloys are often used in hydraulic systems, so copper plates are tested for corrosion to provide information on the aggressiveness of oils. Corrosion on the copper plate may show up as discoloration or flaking. The copper plate is immersed in the test liquid for a specified time at a given temperature (for hydraulic oils 100 °C). The degree of corrosion is evaluated in points: 1 – slight discoloration; 2 – moderate color change; 3 – strong color change; 4 – corrosion (darkening).