Emerging Issues and Fundamental Processes in Environmental Cracking in Hot Water

Abstract

In the absence of definitive data, mechanistic and modeling approaches to describe environmental cracking in high-temperature water are forced to depend too strongly on speculative hypotheses. Because data often exhibit a scatter of a factor of about 1,000, the last two decades have focused on improved and critical experiments and identifying the common threads across many materials and environments. The present data provide excellent insight into many issues, and good insights into others. They also identify new/emerging issues in the broad area of environmental cracking, e.g., related to dK/da, reloading effects, and fracture toughness and tearing resistance. Environmental cracking depends on many interdependent variables, and the only comprehensive way of tackling this problem is to identify the underlying processes that control stress corrosion cracking (SCC). This paper discusses the processes that must be understood and modeled, and the challenges in expanding the predictions to emerging phenomena.