Materials and Corrosion Engineering Tools

This book is a compilation of experiences designed to help readers learn about material degradation occurring mostly in the oil industry through practical examples, where underlying principles are explained on a case-by-case basis. These examples describe the tools used to gather data for determining failure modes; understanding how these tools function is essential for accurately interpreting results. Readers may recognize these phenomena from their own work, even if they have not yet had the opportunity to explore the science behind them in depth.

This volume includes the author's previous research, some of which has not been published externally, while other parts were released as individual pieces rather than within a broader context. For instance, it is argued that High Temperature Hydrogen Attack (HTHA) has primarily been studied at temperatures where pearlite decarburization is evident. However, there is a lack of research on lower-temperature HTHA, where such decarburization is less apparent or does not occur at all. Beyond the cementite plates of pearlite, other more readily carbon sources capable of causing HTHA are present within the Heat Affected Zone (HAZ) of low-carbon steel welds. This explains why HTHA occurs more frequently in the HAZ than in the base metal, for both as-welded (Non-PWHT) and stress-relieved (PWHT) carbon steels.

Metallography remains the most powerful tool for materials and corrosion engineers. This work demonstrates that optical microscopy, SEM, and TEM can reveal the same metallographic features in low-carbon steels, despite their differing underlying principles: while the first two rely on surface topography brough about by etching, TEM directly reveals dislocation substructures and precipitates.