摘要
软化是高温长期运行部件的主要特征,软化意味着材料性能的降低。为了探讨软化对材料低周疲劳特性的影响,对30Cr1Mo1V转子钢进行了应变控制中断低周疲劳试验。试验温度为540℃和565℃,应变幅为0.2%～1.0%,采用拉压对称三角波。基于试验结果,建立了疲劳损伤与低周疲劳寿命之间的关系。通过对试验试样的维氏硬度进行检测,得到了带有硬度修正的低周疲劳应变-寿命修正公式,并对修正公式的有效性进行了检验。结果表明,硬度修正公式在循环寿命小于0.5倍寿命分数时有效,而在循环寿命大于0.5倍时,则存在高估剩余寿命的危险。在同一硬度下,对不同温度和应变,损伤是不同的,应变越小,损伤越大;温度越高,损伤越小。
Degradation is a chief characteristic of high temperature components, which have been operated in high temperature environment for a long time. Degradation means weaken in material properties. In order to study the effect of degradation on the material characteristics in low-cycle fatigue （LCF）, the strain-controlled low-cycle fatigue experiments with intentional interruption were carried out at 540 ℃ and 565 ℃ in steel 30Cr1Mo1V, The strain amplitudes were 0.2 %-1.0 %, and the waveforms were symmetrical triangle. Based on the experiment, the relationship between low-cycle fatigue damage and life fraction is established. By examination of Vicker＇s hardness, the life relationship between life and strain amplitude is proposed of LCF, which considers the hardness modification. The validity examine was made modification is valid only when The results show that hardness the life fraction is less than 0.5, and is overestimated when the life fraction is greater than 0.5. The same hardness has different damage at different strain and different temperature.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2006年第16期133-136,共4页
Proceedings of the CSEE
基金
华北电力大学博士学位教师基金资助(2004-4)
