随着能源短缺问题的不断突出,高参数(高温、高压等)装备的研发成为工业节能降耗的重要手段,如超超临界汽轮机、航空发动机等高端装备。工程实际中,高参数装备的失效多源于缺口等局部不连续部位,其在蠕变-疲劳等复杂载荷下的强度分析和设计是当前研究的热点与难点。系统回顾了蠕变-疲劳载荷下含缺口构件的试验、本构模型、寿命预测、数值分析及考核准则方面的研究进展,主要包括:蠕变-疲劳载荷下的新本构关系及应用;高温强度和寿命分析的新模型及新方法;简化模型试验方法及蠕变-疲劳强度考核准则。总结这一领域的热点和研究展望,可为高参数装备在蠕变-疲劳等复杂载荷下的强度分析与设计提供一定技术支持与借鉴。
With the energy shortage problem more and more serious, the research and development of the high-end equipment (high temperature, high pressure, etc.) is an important measure for energy saving and loss reducing, such as the ultra supercritical steam turbine, aircraft engine and so on. In practical engineering, the failure of much equipment, including the ultra-supercritical steam turbine and aircraft engine, usually originates from notch and some other local structural discontinuities. Its strength analysis and design under complex loadings, such as creep-fatigue loadings, are the main research emphasis and difficulties. In this work, several aspects of notched components subjected to creep-fatigue loading are reviewed, including experimental studies, constitutive equations, life prediction models, numerical analyses and design criteria. Main research progresses are as follows:Some new constitutive models under creep-fatigue loading and their applications, new models and methods for high temperature strength and life analyses, study on simplified model test (SMT) approach and strength criteria of high temperature components under creep-fatigue loading. Current problems and research prospects in future are summarized. The work can provide some technical support and references for strength analysis and design of the high-end equipment under creep-fatigue and other complicated loadings.
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