复合材料螺栓干涉连接摩擦系数影响研究

Study on the Influence of Friction Coefficient of Composite Bolt Interference Connection

干涉连接有助于改善机械连接接头的力学性能,在金属构件中得到了广泛应用,并逐渐推广至复合材料。干涉连接的螺栓初始直径大于孔径,通过螺杆与孔的装配在孔周产生干涉应力,从而改变连接接头在承力时的应力状态。干涉应力的分布不仅与螺栓和孔的材料有关,还受界面摩擦力的影响。本文以碳纤维增强和玻璃纤维增强树脂复合材料为对象,建立螺栓干涉连接有限元模型,对界面摩擦系数分别为0、0.1和0.2时的孔周应力进行分析。研究结果表明:摩擦系数对孔周径向应力和周向应力的分布趋势影响较小,对数值影响较大;减小摩擦系数有助于降低周向应力水平,但会引起径向挤压应力水平的上升。

The interference fit technique is believed to be helpful in improving the mechanical properties of bolts,which are widely used in metal components and extended to composite materials.The initial diameter of the bolt is larger than the hole.So the interference stress is produced around the hole after components assembling,then the stress state of the joint is changed.However,the distribution of interference stress is related to the material and interfacial friction,which should be noticed in analysis.In this paper,the finite element model of interference fit bolted joint is built for carbon fiber reinforced and glass fiber reinforced resin composites.The stress around the hole is analyzed when the interface friction coefficient is 0、0.1 and 0.2.The results show that the friction coefficient has little influence on the distribution trend of the radial stress and circumferential stress,but has obvious effects on the value.The decrease of friction coefficient could reduce the circumferential stress level,but it will cause the increase of the radial extrusion stress level.