This paper discusses the static and fatigue behavior of adhesively bon
ded single lap joints in SMC-SMC composites. Effects of lap length and
adhesive thickness on the static and fatigue strength of SMC-SMC adhe
sive joints are studied. Effects of SMC surface preparation and test s
peed on the joint performance are evaluated. Finally, the effect of wa
ter exposure on the joint durability is also investigated. Results sho
w that the static behavior of adhesive joints in SMC-SMC composites is
significantly influenced by the lap length and adhesive thickness. Wi
th an increase in lap length from 12.7 mm to 38.1 mm, the joint failur
e load increases by 37% The joint failure load also increases with the
adhesive thickness, but it reaches a maximum at an adhesive thickness
of 0.33 mm and then decreases. However, lap length and adhesive thick
ness have negligible effect on the ratio of fatigue strength to static
strength. The fatigue strength at 10(6) cycles is approximately 50% t
o 54% of the static strength for various adhesive thicknesses and lap
lengths investigated in this study. Adhesive failure, fiber tear or co
mbination of these two failure modes are observed during both static a
nd fatigue tests.