环境效应和强化效果对300M超高强度钢疲劳性能的影响

INFLUENCE OF STRENGTHENING EFFECTS AND ENVIRONMENT EFFECTS ON FATIGUE PROPERTIES OF 300M ULTRA-HIGH STRENGTH STEEL

研究了３００Ｍ超高强度钢螺纹滚压和未滚压试样在空气和３．５％ＮａＣｌ的水溶液中的疲劳性能。揭示了环境效应与强化效果的关系。实验发现，在ｆ＝１０Ｈｚ下，滚压件在盐水环境中和未滚压件在空气环境中的应力－寿命曲线之间存在一相交点。应力高于该相交点，强化效果起主导作用；低于该相交点，环境效应起主导作用。

In this paper, the fatigue properties of rolled and non-rolled screw-thread specimens in 300M ultrahigh strength steel in air and 3.5% NaCl water solution were investigated. The relationship of environmental effects and strengthening effects is revealed.It has been found experimentally that an intersection is existed between two S-N curves in saltwater and air at f=10Hz Strengthening effects are acted mainly above the stress levels of the intersection. Environmental effects are acted mainly below the stress levels of the intersection.