ABSTRACT

Surface treatments of primary circuit components in light water reactors are regarded as possible ways to mitigate environmentally-assisted cracking (EAC). To date, it is not fully conclusive which surface condition is suitable to reduce the EAC initiation susceptibility. Constant extension rate tensile (CERT) tests were performed by several labs using flat tapered tensile specimens with different surface conditions (ground, industrial face milled, advanced face milled and shot peened), exposed to a boiling water reactor normal water chemistry environment at 288°C. Despite some scatter in the results, the CERT tests revealed that the EAC initiation susceptibility seems lowest for the advanced face milled surface and highest for the shot peened surface. However, it must be emphasised that the differences were moderate and that the surprising behaviour of the shot peened surface can be explained. The mechanical grinding of the surface did not significantly retard EAC initiation compared to industrial face milling.

摘要

轻水反应堆中一回路部件的表面处理被认为是减轻环境辅助裂化（EAC）的可能方法。迄今为止，尚不能完全确定哪种表面条件适合降低 EAC 引发敏感性。几个实验室使用具有不同表面条件（研磨、工业面铣、高级面铣和喷丸处理）的扁平锥形拉伸试样进行了恒定拉伸速率拉伸 (CERT) 测试，这些试样暴露在 288° 的沸水反应堆正常水化学环境中C。尽管结果有些分散，但 CERT 测试表明，EAC 引发敏感性似乎对于高级端面铣削表面最低，而在喷丸表面最高。然而，必须强调的是，差异是适度的，并且可以解释喷丸表面的惊人行为。与工业端面铣削相比，表面的机械研磨不会显着延迟 EAC 的引发。