What is an important factor for the occurrence of caustic stress cracking in metals?

Caustic stress cracking, often referred to as caustic embrittlement, primarily occurs in metals when they are subjected to high tensile stress in a caustic environment. The presence of caustic substances, such as sodium hydroxide, alongside high tensile stress can induce cracking due to the accelerated reaction of the metal with the caustic solutions. Under these conditions, the metal becomes weaker and more susceptible to cracking because the tensile stress enhances the propagation of any existing microdefects or weaknesses.

In high-stress settings, with the presence of a caustic agent, the likelihood of crack formation increases significantly. This phenomenon is particularly relevant in industrial applications where equipment may be exposed to caustic materials and high mechanical loads. Therefore, understanding and managing operating conditions that may lead to high tensile stress in corrosive environments is critical for preventing failures in metal components.