The importance of removing hydrogen embrittlement after plating
Author:Robby
The importance of removing hydrogen embrittlement after plating is mainly reflected in the prevention of brittle fracture of metal parts in the process of use to ensure the safety and reliability of products. Hydrogen embrittlement is due to the penetration of hydrogen atoms into the metal, especially in the area of stress concentration, the formation of hydrogen molecules to generate a huge pressure, resulting in delayed fracture or sudden brittle fracture of the metal.
The mechanism of hydrogen embrittlement is due to the penetration of hydrogen atoms into the metal during surface treatment such as electroplating and pickling, especially in high-strength steels and elastic parts. Hydrogen atoms diffuse inside the metal, gathered in the stress concentration of the part, the formation of hydrogen molecules, generating a huge pressure, more than the yield strength of the metal, resulting in the fracture of the metal.
Specifically, the reasons for post-plating hydrogen removal treatments include:
Preventing hydrogen embrittlement: During the plating process, hydrogen ions are reduced to hydrogen atoms that penetrate into the metal. Without dehydrogenation treatment, these hydrogen atoms will accumulate inside the metal, leading to hydrogen embrittlement and affecting the toughness and strength of the metal.
Ensure product quality: Hydrogen removal significantly reduces the likelihood of hydrogen embrittlement and ensures the quality and safety of plated products, especially in high corrosion resistance and high strength applications.
Avoiding safety hazards: For hydrogen-sensitive materials such as high-strength structural steels and elastomeric parts, dehydrogenation prevents sudden breakage during use and ensures the safe use of the product.
The method of dehydrogenation is usually by heat treatment, in which metal parts after plating are placed in a high-temperature oven, heated and held for a period of time, so that the permeated hydrogen atoms can rediffuse back to the surface and be released from the metal. The exact temperature and time varies according to different materials and shapes, but it is generally held between 200-300°C for 2-4 hours.