白铜弹簧丝两级载荷下累积疲劳损伤预测模型

通过对文献中白铜弹簧丝疲劳寿命试验数据的分析，给出了具带存活率的疲劳寿命曲线表达式。在此基础上，建立了两级载荷下累积疲劳损伤及概率分布的预测模型。

Calculation of Needle Valve Seating Stress for Fuel Injector of Diesel Engine

This paper presented a formula which is derived from the theory of strain wave, to calculate the seating stress for the low mass fuel injector without push rod. It was illustrated that the calculating results by the formula well tallied with those in practice. It illustrated that the calculating results by the formula well tallied with those in practic. Therefore the formula could be taken as a trusty basis to design a nozzle and to select the needle valve opening pressure for the fuel injector without pust rod. Meanwhile, the new formula presented in this paper also solves the contradiction which the needle valve opening pressure used in practice is not accordance with the one calculated from the old formula.