The Effect of BWR Startup Environments on Crack Growth in Structural Alloys
The Effect of BWR Startup Environments on Crack Growth in Structural Alloys
复制标题
沸水堆启动环境对结构合金裂纹扩展的影响
DOI：
10.1115/1.3225840
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
D. A. Hale
中科院分区：
文献类型：
--
作者：
D. A. Hale
在沸水反应堆（BWR）的启动过程中，水的化学性质和温度不断变化。可以进行特殊的操作实践以控制溶解氧水平，例如使用真空脱气。为了评估启动实践对沸水堆中使用的结构材料中的环境开裂的影响，执行了一个大型程序，以评估常规和真空除气启动实践在代表性环境条件下的裂纹增长。研究了五种合金：304和316型核级不锈钢、Inconel 600、碳钢和A508-2低合金钢。使用断裂力学型试样进行试验，在适当的应力强度水平下测量恒定载荷裂纹扩展。该计划旨在比较两种做法的裂纹扩展速率。结果表明，正常启动和启动除氧环境有不同的影响。敏化型304不锈钢在低温脱气条件下，裂纹扩展速率降低，晶间断裂形态严重程度随之降低。相比之下，316型核级由于其固有的抗应力腐蚀开裂性，启动脱气的影响很小。Inconel 600在脱气环境中的裂纹扩展速率降低了5倍。«少
During startup of a boiling water reactor (BWR), the water chemistry and temperature are constantly changing. Special operational practices can be performed to control the dissolved oxygen level using, for example, vacuum deaeration. To assess the impact of startup practice on environmental cracking in the structural materials used in the BWR, a large program was performed to evaluate crack growth at representative environmental conditions for both conventional and vacuum deaeration startup practices. Five alloys were studied: types 304 and 316 nuclear grade stainless steel, Inconel 600, carbon steel, and A508-2 low alloy steel. Tests were performed using fracture mechanics type specimens with constant load crack growth measured at appropriate stress intensity levels. The program intent was to compare the crack growth rates for the two practices. The results show that normal startup and startup deaeration environments had varied effects. Sensitized type 304 stainless steel exhibited a decrease in crack growth rate and concomitant decrease in severity of intergranular fracture morphology at the low temperatures under deaeration. In contrast, the type 316 nuclear grade displayed very little influence of startup deaeration due to its inherent resistance to stress corrosion cracking. Inconel 600 showed up to a factor of five reduction inmore » crack growth rate in the deaeration environment.« less