After the accident, considerable investigations have been taken on SCC phenomenon. In fact, the industry owners did not find the austerity of the problems connected to the stress corrosion cracking until the tragic rupture of a digester at Pine Hill, Alabama, in 1980. Identification of SCC occurred between 1930s and 1950s, the mechanism of SCC was explained between 1960s and 1970s and its application and development began at 1980s. Stress corrosion cracking (SCC) is service failure of engineering materials that occurs by slow, environmentally induced crack propagation. The main objective in writing of this chapter is to present scientific findings and relevant engineering practice involving this phenomenon. , which properly describes the fracture behavior of materials in such conditions. The fracture mechanic introduces a material characteristic namely fracture toughness or Therefore, when designing components, the role of imperfections and aggressive agents together must be taken into account. Presence of crack and other defects on the material surfaces accelerates the fracture processes. Two classic cases of stress corrosion cracking are seasonal cracking of brass in ammoniacal environment and sensitization and stress corrosion cracking of stainless steels in existence of chlorides, caustic, and polythionic acid. It can also occur after several years of satisfactory services due to operating errors and changing process conditions. The fractures are often sudden and catastrophic, which may occur after a short period of design life and a stress level much lower than the yield stress. Stress corrosion cracking is a phenomenon associated with a combination of tensile stress, corrosive environment and, in some cases, a metallurgical condition that causes the component to premature failures.
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