基于可靠度的Incoloy800H管材蠕变性能分析

The Analysis on Creep Property of Incoloy800H Tube by Reliability Concept

摘要:

结合蠕变特征量-温度参数模型,研究了Incoloy800H管材在600℃-1050℃下的蠕变行为,拟合得出材料稳态蠕变速率、蠕变断裂时间、蠕变第三阶段起始时间的可靠性方程,并建立了管材容许应力与服役温度、可靠度的关系。结果表明,确定的蠕变特征量可靠性方程可以较好地预测Incoloy800H管材稳态蠕变速率、蠕变断裂时间、蠕变第三阶段起始时间的变化行为。长时蠕变数据均位于对应蠕变方程在可靠度0.997条件下的预测区域内。与ASME推荐的容许应力值相比,蠕变特征量可靠性方程可以提供更为准确的容许应力评估结果。

Abstract:

In order to take full advantage of Incoloy800H alloy, the creep behavior of Incoloy800H alloy tubes at temperatures ranging from 600℃to 1050℃ was investigated based on creep character-temperature parameter models. The reliability equations of steady creep rate, rupture time and initiation time of tertiary creep were obtained by multiple linear regression. The effective relationships among allowable stress, service temperature and reliability were established. The results demonstrate that the creep reliability equations make the prediction for creep behavior of Incoloy800H alloy tubes more accurately. The long-term creep data are completely located in the 0.997 confidence band of predicted results by corresponding reliability equations. In comparison with recommended allowable stresses by ASME, the creep reliability equations can provide more reasonable evaluated results.