摘要
In order to estimate the cavitation incubation period of duplex stainless steel(DSS)under ultrasonic cavitation erosion(CE),this paper analyzed the loading process of material during ultrasonic CE.Local strain theory,cumulative damage theory,and Bernoulli probability model were used to derive the minimum number of cavitation impacts required for the initiation of fatigue cracks,and the predictive equation of the material cavitation incubation period was given.DSS was obtained by tungsten inert gas welding(TIG)powder surfacing method.Tensile test and ultrasonic CE test were performed,and the tensile test data were used to calculate the cavitation incubation period by using the predictive equation.Due to the possible presence of precipitates and micro-cracks in the sample,there was an error between the calculated and the test results.The results showed that the max error between the calculated results and the test results was 8.1%,and the errors of the remaining two groups were within 3.5%.
为了估算在超声波空蚀条件下不锈钢的空蚀孕育期,本文分析了空蚀过程中试样的受载过程,使用局部应变理论和累计损伤理论,并结合伯努利概率模型,推导了使材料萌生疲劳裂纹所需的最小空泡冲击数,并给出了材料空蚀孕育期的估算公式;通过TIG粉末堆焊的方法制作了双相不锈钢试样,对其进行拉伸和超声波空蚀,将拉伸数据用于空蚀孕育期计算;结果表明因实际测量精度,以及试样中可能存在的析出相和微裂纹的影响,会使计算结果出现一定程度的误差,最大误差为8.1%,其余两组误差均在3.5%以内.
基金
This work was supported by the National Natural Science Foundation of China(Grant No.51879089).