摘要
应用平衡晶界偏聚理论推算2.25Cr-1Mo钢杂质原素P晶界偏聚量的等脆化曲线。随着脆化度的增加,等脆化曲线向着低温长时间方向移动,并且具有一临界脆化温度与之对应,高于此温度的后续热处理为脱脆过程,反之为脆化过程。试验结果与本文理论对比分析表明:应用平衡晶界偏聚理论、等效时间概念及等脆化曲线可以定性和定量的分析材质连续脆化或脱脆机理。随着材质脆化加深,其临界脆化温度向着低温方向移动,起初加速脆化的步冷试验或修正步冷试验逐渐变成脱脆过程。理论计算表明运行5年和12年的加氢反应器材料临界脆化温度分别为526℃和505℃。
The constant embrittlement curve for constant segregation concentration of impurity element P on grain boundary in 2.25Cr-1Mo steel was derived based on the theory of equilibrium grain boundary segregation.The curve moves to the direction of low temperature and long time with increase of embrittlement.There is a critical temperature of embrittlement corresponding to each of the constant embrittlment curves.When the further heat treating temperature is higher than the critical temperature,a de-embrittlement process operates. Otherwise, it will be an embrittlement process. The further heat treatment tests were conducted to compare with the theory calculation, and the results show that the mechanism of further embrittlement or de-embrittlement can be explained by theory of equilibrium grain boundary segregation, equivalent time and constant embrittlement curve. The critical temperature of embrittlement shifts to the direction of low temperature with further embrittlement, and as a result, the step-cooling test and modified step-cooling test gradually changes into a de-embrittlement process. The critical embrittlement temperature of hydrogenation reactor steel after service for 5 or 12 years is 526℃ and 505℃, respectively.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2009年第4期194-197,共4页
Transactions of Materials and Heat Treatment
关键词
等脆化曲线
平衡晶界偏聚
临界脆化温度
脆化机理
constant embrittlement curve
equilibrium grain boundary segregation
critical embrittlement temperature
embrittlement mechanism
