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The reaction product hydrogen is generally believed to have two possible fates: one is that hydrogen atoms have a strong affinity for each other, allowing them to combine to form hydrogen molecules that are then released； Another fate is that hydrogen atoms, which have an extremely small atomic radius, acquire sufficient energy to turn into diffuse hydrogen, which then penetrates into the steel and dissolves into its lattice. Hydrogen dissolved in the lattice is highly mobile, and under certain conditions it can cause the material to become brittle (hydrogen embrittlement) as well as induce hydrogen-induced damage. 1. Hydrogen pressure theory: Similar to the reasons behind hydrogen-induced bubbling, hydrogen pockets formed at inclusions, grain boundaries, and other locations can generate significant internal stresses. These stresses cause microcracks to form within materials with high strength. Driven by stress gradients, hydrogen atoms accumulate in the triaxial tensile stress region at the tips of these microcracks, thereby \"pinning\" dislocations in the crystal lattice and reducing the plasticity of the steel. When the tensile stress caused by internal pressure together with the hydrogen concentration at the crack tips reaches a certain critical value, the microcracks expand. Hydrogen then accumulates again at certain points along the expanded crack tips, leading to further crack growth, and this ultimately results in fracture. 2. Types of cracking in wet H2S environments: Hydrogen bubbling (HB), Hydrogen-induced cracking (HIC), Sulfide stress corrosion cracking (SSCC), Stress-oriented hydrogen-induced cracking (SOHIC). Several typical forms of hydrogen damage in acidic environments