玻璃纤维增强树脂基复合材料弯曲强度时间温度相关性

研究了玻璃纤维增强树脂基复合材料 (GFRP) 层合板弯曲强度高温加速试验的时间温度相关性。在不同的温度和加载速率下进行了三点弯曲试验。通过弯曲强度控制曲线的时间温度移动因子曲线分析了GFRP层合板的弯曲强度时间温度相关性。探讨了低温短时和高温长时的失效机理。通过玻璃纤维拉伸延迟断裂试验,对GFRP层合板的低温短时弯曲强度的时间温度相关性进行了修正。修正后的弯曲强度控制曲线的时间温度移动因子曲线与基体树脂动态杨氏模量的时间温度移动因子曲线非常吻合,表明GFRP层合板的弯曲强度取决于基体树脂的粘弹性性能。 

TIME-TEMPERATURE DEPENDENCE OF FLEXURAL STRENGTH OF GLASS FIBER REINFORCED PLASTICS

The time-temperature dependence of flexural strength of glass fiber reinforced plastics(GFRP,volume fraction of glass fiber:57%) laminates was studied by the accelerated testing method at high temperatures.The three-point bending tests were carried out at various temperatures and constant loading rates.The time-temperature dependence of GFRP laminates was investigated by means of the flexural strength master curve and time-temperature shift factor curve.The failure mechanisms at low temperature for short time to failure and at high temperature for long time to failure were investigated.With tensile delay fracture tests of the glass fiber,the time-temperature shift factors of flexural strength at various low temperatures for short time to failure were modified.The revised time-temperature shift factor curve of flexural strength of GFRP laminates agrees well with that of the dynamic Young's modulus of the resin matrix.The flexural strength of GFRP laminates depends strongly on the viscoelasticity of the resin matrix.