Fatigue behaviour of composite adhesive lap joints

Abstract This paper is concerned with a fatigue study of composite adhesive lap joints produced from a bi-directional woven E-glass fibres and polypropylene. The adhesive used was a Bostik 7452 (Rubber & Plastics Grade) ethyl cyanoacrylate type. The effects of layer orientation, lap joint length and water immersion on the fatigue behaviour were studied. The specimens were immersed in water during periods until ninety days for controlled temperatures of 20, 40 and 70 °C. The results are presented in the form of curves of stress amplitude versus number of cycles to failure and also in the form of number of cycles to failure against time to exposure in water for fixed stress amplitudes. The fatigue damage and failure mechanisms were analysed and discussed. The joint shows that creep deformation within the temperature range of this study was probably the mainly cause of the dynamic stiffness reduction observed.

[1]  T. Guess,et al.  COMPARISON OF LAP SHEAR TEST SPECIMENS , 1977 .

[2]  W. Bradley,et al.  Effects of seawater absorption on fatigue crack development in carbon/epoxy EDT specimens , 1995 .

[3]  J. Comyn,et al.  The durability of some epoxide adhesive-bonded joints on exposure to moist warm air , 1980 .

[4]  Jack R. Vinson,et al.  The Efficient Design of Adhesive Bonded Joints , 1975 .

[5]  J. Cognard.  Influence of water on the cleavage of adhesive joints , 1988 .

[6]  L. Carlsson,et al.  Influence of Water Absorption on Transverse Tensile Properties and Shear Fracture Toughness of Glass/Polypropylene , 1996 .

[7]  J. Ferreira,et al.  Static and fatigue behaviour of glass-fibre-reinforced polypropylene composites , 1999 .

[8]  J. Vinson,et al.  On the behavior of bonded joints in composite material structures , 1975 .

[9]  M. Bowditch,et al.  The durability of adhesive joints in the presence of water , 1996 .

[10]  José Costa,et al.  Analysis of fatigue and damage in glass-fibre-reinforced polypropylene composite materials , 1999 .

[11]  R. I. Mackie,et al.  The effects of ageing and environment on the fatigue life of adhesive joints , 1992 .

[12]  P. A. Fay,et al.  Fatigue life evaluation of structural adhesives for automative applications , 1992 .

[13]  N. Dowling.  Mechanical Behavior of Materials: Engineering Methods for Deformation, Fracture, and Fatigue , 1993 .

[14]  F. L. Matthews,et al.  The influence of stacking sequence on the strength of bonded CFRP single lap joints , 1985 .

[15]  Robert D. Adams,et al.  The effect of temperature on the strength of adhesive joints , 1992 .

[16]  Anthony J. Kinloch,et al.  Developments in adhesives , 1977 .

[17]  S. Mall,et al.  Effect of bond thickness on fracture and fatigue strength of adhesively bonded composite joints , 1989 .

[18]  J. Vinson,et al.  Fatigue Behavior of Bonded Joints in Composite Material Structures , 1975 .