Metallic components form a surface __________ when exposed to sulfur compounds. This may react with air (oxygen) and moisture to form sulfur acids (polythionic acid).

Which of the following materials are susceptible to polythionic acid SCC?

_________ is surface initiated cracks caused by environmental cracking of 300 Series SS and some nickel based alloys under the combined action of tensile stress, temperature and an aqueous chloride environment. The presence of dissolved oxygen increases the propensity for cracking.

Which of the following materials is affected by high temperature corrosion?

Carbon steel is susceptible to SCC when used in ___________ service.