Stress corrosion cracking is defined as the delayed failure of alloys by cracking when exposed to certain environments in the presence of static tensile stress. The importance of a conjoint action of corrosion and stress is reflected in the definition; an alternate application of stress and corrosive environment will not produce stress corrosion cracking. The stress level at which the failure occurs is well below the stress required for a mechanical failure in the absence of corrosion. The minimum stress below, which stress corrosion cracking occurs, is called the threshold stress.