API 571 Certification (Corrosion & Materials) 2025 – 400 Free Practice Questions to Pass the Exam

The material that is particularly vulnerable to embrittlement in high temperature applications is 400 series stainless steel. This type of stainless steel, which includes materials primarily composed of ferritic and martensitic structures, can suffer from embrittlement due to the formation of hard, brittle phases such as sigma phase and embrittling carbides in elevated temperature environments.

In high temperature scenarios, 400 series stainless steels can lose ductility and toughness as they undergo phase transformations and precipitate formation, which compromises their structural integrity. This susceptibility becomes more pronounced when the materials are exposed to prolonged elevated temperatures, leading to issues such as stress corrosion cracking and hydrogen embrittlement.

While duplex stainless steels, 300 series stainless steels, and nickel alloys have their own vulnerabilities, they generally exhibit better resistance to embrittlement in high temperature applications compared to 400 series stainless steels. Duplex stainless steels are designed to withstand higher temperatures due to their dual-phase microstructure, while 300 series alloys are austenitic and retain ductility. Nickel alloys also tend to perform well in high-temperature applications due to their excellent resistance to oxidation and scaling.