The Research On Mechanical-joint Technology Of Composite Laminate

Composite material has a lot of virtues which common material has no means of analogic merits, and mechanical-joint composite laminate is one of most important joint form, the technology of mechanical-joint composite laminate has been systemically studied in this paper.First of all, making use of ANSYS software, the pin load distribution of multiple bolt-joint composite laminate has been studied. The characteristic of composite material, the friction and contact between the bolts and composite laminate, the preload of the composite laminate, and the boundary conditions of bolts and composite laminate have all been considered in this process of analysis. The calculated results are in good agreement with experiment data. This shows that the pin load distribution can be well analyzed by ANSYS software. Studying result shows the following important points. It is very asymmetrical of the distribution of pin load of multiple slip-joint.The second, making use of ANSYS software, the pin load distribution of multiple Swage-locking pin-joint composite laminate has been studied. The process of interference-fit between swage-locking pin and composite laminate has been analyzed by introducing the static state contact arithmetic. The calculated results are in good agreement with experiment data. This shows that the pin load computations can be well analyzed by ANSYS software. Studying result shows the following important points. Comparing with sliding-fit composite joint, interference-fit composite joint can certainly obtain more symmetrical pin load distribution.The third, making use of Finite Element Method, experiment and academic analysis, the influence of stress concentration, residual stress and preload on fatigue life of interference-fit composite joint has been studied. The result shows the following important points. The fatigue life of interference-fit composite joint is greatly longer than the fatigue life of sliding-fit composite joint;the fatigue life of interference-fit composite joint has been affected highly by interference quantity;the notch coefficient of interference-fit composite joint is less than the notch coefficient of sliding-fitcomposite joint;there is upper residual compressive stress at assort position of interference-fit composite joint;preload redound to remit notch coefficient of interference-fit composite joint;in company with the aggrandizement of the preload, the stress concentration factor of composite has slowness wane.At last, making use of ANSYS software, the contact stress of pin and composite laminate has been studied. Studying result shows that the fatigue life of the interference-fit composite laminate will not be advanced, when bend has existed.