Exam API-571 All QuestionsBrowse all questions from this exam
Question 88

Oxidation of carbon steel begins to become significant above _________.

    Correct Answer: C

    Oxidation of carbon steel becomes significant above 1000º F. At this temperature, the iron oxide layer that forms is less protective and more likely to crack, which exposes the underlying steel to further oxidation.

Discussion
ahmadmmOption: C

Oxidation of carbon steel begins to become significant above about 1000 °F (540 °C). Rates of metal loss increase with increasing temperature. At temperatures above about 1000 °F (540 °C), the oxidation of carbon steel becomes significant. This is because the iron oxide layer that forms at these temperatures is less protective than the oxide layer that forms at lower temperatures. The higher temperature oxide layer is also more likely to crack and expose the underlying steel to further oxidation.