ABSTRACT

The applicability of an accelerated test technique using tapered tensile specimens for investigating the stress corrosion crack (SCC) initiation behaviour of structural materials in high-temperature water was assessed in the framework of a European collaborative research project (MICRIN – MItigation of CRack INitiation). The main advantage of using a tapered geometry is, that in a single test a stress gradient is obtained through the gauge length, and therefore a stress threshold for SCC initiation can be determined in a reasonable timeframe. This method was used to investigate two different materials that were known to be susceptible to SCC in light water reactor environment: a high-Si stainless steel and a Ni-base weld metal (Alloy 182). The results of the international test programme confirmed that the tapered specimen test methodology could be used to identify a SCC initiation stress threshold, albeit that significant scatter was present in the data.

摘要

在一项欧洲合作研究项目（MICRIN – CRack Initiation的缓解）的框架内，评估了使用锥形拉伸试样测试加速材料在高温水中的应力腐蚀裂纹（SCC）引发行为的加速测试技术的适用性。使用锥形几何形状的主要优点是，在单个测试中，可以通过标距获得应力梯度，因此可以在合理的时间范围内确定SCC启动的应力阈值。该方法用于研究两种在轻水反应堆环境中易受SCC影响的不同材料：高硅不锈钢和镍基焊接金属（合金182）。