经受低幅交变载荷后车辆零件屈服强度增长规律的研究

RESEARCH ON THE INCREASING RULES OF YIELD STRENGTH OF VEHICLE PARTS AFTER LOW AMPLITUDE LOADING

在试验研究的基础上拟合出零件在经受多次低幅交变载荷后，屈服强度随交变载荷大小及其循环次数而变化的关系方程。藉此方程，可较合理地描述零件在经受低幅交变载荷作用后的屈服强度增长规律，为疲劳试验和寿命预估中确定删除小载荷的原则提供了一定依据，也有助于车辆结构件的减重设计。

Many structural parts of farm vehicles are to be worked under a large number of alternating loads with low amplitude. However people seldom pay enough attention to the effect of the loads on parts strength, especially the effects on parts static strength are still blurred and many problems need to be solved. In fact, under alternating load, the strength of parts will continuously change which seriously affects the working condition of vehicles. Based on a series of tests and researches, an equation describing the relations among yield strength, low load amplitude and load cycles was derived. The increasing rule of parts yield strength after low amplitude loading can be determined by means of the equation. Further more, the principles of deleting low amplitude load in fatigue testing and life predicting can be defined according to the equation, and it is also helpful in the lightening design of vehicle parts.