The prestressed steel wire and steel strand, copper plating, phosphating treatment, and blackening dyeing process used in the Japanese factory were researched and discussed. Now, overseas research dreams have also been proposed regarding the copper content in the motion component's ability to prevent corrosion. The tensile stress of the steel and the corrosive medium act together. That is, tensile stress causes the grains of the prestressed steel strand to slip. When there is a corrosive medium, the material between the grains is destroyed, causing intergranular cracks in the steel and expanding along the grain boundaries. Stress corrosion cracking occurs suddenly without obvious signs, leading to greater damage.

Now, stress corrosion has become the primary policy for evaluating the performance of prestressed steel, and it is highly valued by countries worldwide. The emergence of zinc-coated prestressed steel wire strands is an effective method to delay wire corrosion and stress corrosion. When the wire strand surface has defects reaching the steel base or shows some corrosion pits, the galvanized wire will experience hydrogen embrittlement and cracking. Due to the high strength and low plasticity of prestressed steel wire, it is more prone to corrosion than general steel. If affected by rain, moisture, or corrosive substances during storage and transportation, prestressed steel can undergo electrochemical corrosion, causing the wire to form scattered corrosion pits. These pits are akin to "notches." During tensioning, unevenly distributed stress in the wire strand creates stress at the "notch" edges. When the uniform stress is low, the stress at the "notch" edges has reached the fracture stress, leading to early cracking. The notch activation effect caused by corrosion is related to the arrangement of the steel. When the carbon content is high and the residual stress is high, the "notch" becomes more active in terms of stress.