Study On The Creep Performance Of Flexible Graphite Corrugated Metal Gaskets Under Fatigue Loading

High temperature and fatigue load are usually exist in the working environment of flexible graphite corrugated metal gasket,and high temperature and fatigue load have great impact on the performance of the metal skeleton of the gasket.There is no structural parameters standards ofthe metal skeletonof the gasketat present.The performance of the gasket with different fatigue loads and different temperatures was studied based on the experiment.The part of the test data was introduced into the finite element software,thevariation of structural parameters of the metal skeleton were studied.Divided fatigue load into different cyclic loading and unloadingstress ratio and different cyclic loading and unloading rates.The compression resilience of 304 stainless steel under different cyclic loading and unloading stress ratio at 500 ? were researched,the cumulative strain and cumulative strain rate of 304 stainless steel samples were obtained.The experiment ofthe effect of different loading and unloading rates on compression resilience performance of the gasket at 500? were conducted,and the formula of compression resilience curve based on cyclic loading and unloading rate were obtained.Thecyclic loading and unloading tests of gaskets at temperatures of 100? and 300? were conducted.Based on the measuredstress-strain data and the calculation of cyclic compression modulus and cyclic unloading modulus,the compression resilience characteristics of the gaskets were analyzed.Considered the influence of the temperature and the thickness,the effects of interaction between creep and fatigue on the gaskets were explored.The result shows that the cumulativecompression displacement of the gaskets decreases and the resilience displacement of the gaskets decreases with the increasing oftime under fatigue load;in the steady creep stage,the creep curve of the gasket appears ratchet effectunder the interaction between creep and fatigue.The non-linear elasticity data of the first loading and unloading cycle was extracted from the experiment of 304 stainless steel under different cyclic loading and unloading stress ratio at 500?.The data was introduced into the ANSYS as a elastic-plastic material characteristics of 304 stainless steel at 500?.the effect of the changes of the structure parameters on the performance of the metal skeleton were researched by using ANSYS.The result shows that the changes of the tooth width has greater influence in the stress and strain state of metal skeleton than the changes of tooth radius and tooth depth,and the influence of the changes of tooth radius and tooth depth at the same level.