API 571 Certification (Corrosion & Materials) Practice Test

What is the primary concern with weld materials in terms of temper embrittlement?

1. They are less affected than base materials

2. They are generally more affected

3. They cannot undergo metallurgical changes

4. They are entirely resistant

The correct answer is: They are generally more affected

Temper embrittlement is a phenomenon that typically affects certain weld materials—especially those that are high in carbon and low in alloy content—leading to a decrease in ductility and impacting the mechanical properties significantly. The primary concern with weld materials in terms of temper embrittlement is that these materials are generally more affected due to their unique composition and microstructure changes that occur during welding processes. Welded joints often experience different thermal cycles compared to the base materials, which can lead to the segregation of certain elements (such as phosphorus or antimony) at the grain boundaries. This segregation can subsequently result in embrittlement, making these welds more susceptible to failures under stress or impact loading. A clear understanding of this concern is crucial for engineers and materials specialists, as it influences the choice of welding processes, filler materials, and post-weld heat treatments aimed at mitigating the risk of temper embrittlement in critical applications.