304 stainless steel pipe stress corrosion failure / a batch of 304 stainless steel pipe purchased by the customer has cracked and leaked after a period of use, and the customer raised a quality objection. The batch of 304 stainless steel pipes purchased by the customer are used as steam condensate return pipes and are buried underground. The stainless steel pipe has been used for half a year, and the cracked and leaked part was detected as transcrystalline stress corrosion cracking. The corrosion rate of 304 stainless steel in the soil is very low, so it is not normal for stress corrosion cracking to occur in a short time. The conditions for stress corrosion cracking are that there is a medium that induces pitting corrosion, such as a chloride ion or sulfur environment, and then there is a tensile stress. After observation, part of the pipeline line that leaked crosses a highway, and the city generally uses antifreeze salt to melt snow after it snows in winter. The antifreeze salt dissolves and penetrates into the soil where the pipeline is located, plus the pipeline has thermal expansion and cold The existence of shrinking stress eventually leads to stress corrosion cracking. The reason for this case is that the use environment of stainless steel has not been fully considered, so other materials of pipes should be replaced, or protective measures should be strengthened on the pipeline near the highway side.