Monitoring power-law creep using the Failure Forecast Method
Monitoring power-law creep using the Failure Forecast Method
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DOI：
10.1016/j.ijmecsci.2018.02.041
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发表时间：
2018-05-01
影响因子：
7.3
通讯作者：
Davies, C. M.
中科院分区：
文献类型：
--
作者：
Corcoran, J.;Davies, C. M.
蠕变被认为是许多承载高温部件的寿命限制损坏机制。一系列不同的参数决定了部件的蠕变寿命，其中许多参数不太可能以足够的准确度已知，无法对剩余寿命进行令人满意的估计。相反，应通过直接测量部件对操作条件的响应来确定部件的完整性。蠕变变形被证明是一个正反馈机制，应变的增加导致应变速率增加。最近已经表明，作为正反馈的结果，故障预测方法，一个通用的框架，用于预测时间的关键的基础上的变化率的损害，可以应用于剩余寿命计算。在文献中已经提出了一系列基于应变率的评估，但建议失效预测方法统一了许多这些技术，并通过潜在的正反馈提供了对蠕变行为的额外见解。该方法已被证明使用相关的高温压力容器和管道蠕变的实验数据集，它示出的故障时间准确预测后不久的最小蠕变应变率。(C)2018作者爱思唯尔有限公司出版
Creep is considered to be the life limiting damage mechanism in many load bearing high temperature components. A range of different parameters determine the creep life of a component, many of which are unlikely to be known to sufficient accuracy to enable satisfactory estimation of remnant life. Instead, the integrity of a component should be established through direct measurement of the response of the component to the operating conditions. Creep deformation is shown to be a positive feedback mechanism; an increase in strain leads to an increasing strain rate. It has recently been shown that as a consequence of positive feedback the Failure Forecast Method, a generalised framework for predicting time to criticality based on rates of change of damage, may be applied for remnant life calculations. A range of strain rate based assessments have been proposed in the literature but it is proposed that the Failure Forecast Method unifies many of these techniques and provides additional insight into creep behaviour by virtue of the underlying positive feedback. The methodology has been demonstrated using experiment data sets that are pertinent to creep in high temperature pressure vessels and piping; it is shown that failure times are accurately predicted shortly after the minimum creep strain rate. (C) 2018 The Authors. Published by Elsevier Ltd.