Effects of adhesion on the effective Young's modulus in glass slide/glue laminates: Part I. Experiments

Bond-phase defects in laminates can affect the mechanical properties of laminate composites. The effects of adhesion area, number of glue spots, and bond thickness on the effective Young's modulus of adhered microscope glass slides have been investigated. Three different adhesive agents (super glue, epoxy cement, and epoxy resin) were used to explore the effect of bond-phase defects upon adhesion in laminates. The elastic moduli of single glass slides, unadhered glass slide pairs, glass slide/glue composite specimens and epoxy resin specimens were non-destructively determined by a sonic resonance technique. The change of Young's modulus of adhered glass slides was monitored while adhesion area per cent ranged from 0.35-100%. Trends in the Young's moduli of glass slide/glue composite specimens have been analysed by a least-squares best-fit procedure to two empirical equations. Qualitative explanations for the observed trends are discussed.