Papers by Keyword: Bonded Structure

Abstract: 3-layer anodic bonding is one of the key technologies in the manufacture of complicated structure. The microcosmic process and current model of the 3-layer anodic bonding was investigated, and a new technology scheme with better bonding effect was developed. Using the experiment device, quantities of bonding current curves were obtained by the data collecting system. Under tensile testing device, intensity of the bonding was tested. By analysis of the data collected, the 3-layer bonding model was inspected, and the efficacy of the new technology scheme was proved.

Abstract: The application of adhesively bonded straps made of high-static strength materials on aeronautical stiffened panels to retard the fatigue skin crack growth is currently a topical research subject. The detrimental effect of the residual stress fields induced as a consequence of the dissimilar coefficients of thermal expansion of the skin and strap materials on the fatigue skin crack propagation was investigated. The residual stresses induced in a stiffened panel representative of a pressurized fuselage shell with titanium doublers in the middle of the stringer bays is numerically quantified for two likely operational temperatures. Their effect on the fatigue crack propagation is analyzed by means of a linear elastic fracture mechanics approach. The results show that adhesively bonded straps on the cracked surface can significantly retard the fatigue crack propagation but, in order to achieve reliable and conservative predictions on their performances, the effect of the residual stress fields they introduce must be taken into account.