利用声发射技术对T300/QY8911树脂基复合材料不同铺层角度层合板的静态拉伸,静态拉伸中的分段加卸载,低周疲劳试验进行全程监测,通过声发射多参数分析法综合分析了试样在3种试验中的损伤形式以及损伤演变过程之间的联系。结果表明:铺层角度决定了试样的拉伸强度,不同铺层角度的试样对应着不同的损伤破坏过程和声发射信号特征。加卸载试验分段再现了静态拉伸中试样的损伤演变过程,弗利西蒂比(Felicity)的变化反映出的试样损伤情况与静态拉伸试验中试样声发射事件的幅值和能量变化所反映出的损伤破坏情况类似。试样在疲劳载荷作用下的声发射事件数和声发射能量值表明第一循环相当于同等应力水平的静态拉伸作用。主要损伤集中在前100循环,产生大量的声发射事件和较高的能量。
The acoustic emission (AE) technology was used to monitor the damaging progress of T300/QY8911 resin matrix composites with different ply stacking angles under tensile, stepwise incremental loading and unloading and low cycle fatigue loading. The damage types and the relation of different progresses of damaging evolution were revealed by AE multi-parameter analysis. Experimental results indicate that the intensity of the composites is determined by the ply stacking angles. Different ply stacking angles are corresponding to different damaging process and acoustic emission characteristics. The results of stepwise loading and unloading replay the damaging process of samples under tensile loading. The damaging situation reflected by the variation of Felicity is similar to the damaging process reflected by the evolution of AE hits, AE energy, and AE amplitude under tensile loading. The number of AE hits and the value of cumulative AE energy in the first cycle under cyclic loading is equivalent to the effect of tensile loading in the same level of stress. The main damage concentrates in the first 100 cycles and the samples have generated a great amount of AE hits and high quantities of AE energy.