2.5维机织复合材料的纬向力学性能试验

通过室温(20℃)及高温(180℃)静态拉伸及拉 拉疲劳试验,获得了25维树脂基机织复合材料在不同温度下的力学性能及拉 拉疲劳寿命。基于宏观试验,探讨了材料在静载及拉 拉疲劳载荷作用下的破坏模式和失效机理,对比了材料在疲劳载荷作用后的剩余强度与静强度的关系,之后分析了温度对材料静态力学性能及疲劳寿命的影响。结果表明:在20~180℃温度范围内材料的纬向模量对温度不敏感,但纬向强度及疲劳寿命随温度的升高而显著下降。在高温高应力水平（高于80%静强度）下材料的纬向疲劳寿命非常短(小于104次循环),但当应力水平仅下降2%后,材料的纬向疲劳寿命趋于106次循环。另外,高温下材料的剩余强度大于高温静强度。 

Test of the weft mechanical properties of 2.5D woven composites

The mechanical properties and tension tension fatigue life of 25D resin base woven composites at various temperatures, including room temperature (20℃) and high temperature (180℃), were obtained by static tensile and tension tension fatigue tests. Based on macroscopic tests, the damage modes and failure mechanism of the materials subjecting to static tensile and tension tension fatigue loadings were discussed. Meanwhile, the relationship between residual strength and static strength was compared, and the influence of temperature on the static tensile and fatigue life was then analyzed. The results show that the weft modulus is not sensitive to temperature, ranging from 20℃ to 180℃, but the weft strength and fatigue life have a downward trend with the temperature increase. The weft fatigue life experiences a quite short cycle (less than 104 cycles) prior to the ultimate failure at high temperature and high stress level (higher than 80% static strength), however, the corresponding life tends to be 106 cycles when the stress level declines by only 2%. Additionally, the elevated residual strength is higher than the static strength tested at the same temperature.