| Four isotropic conductive adhesives (ICAs 1-4) were studied as a replacement for solder in electronics assembly. Cure behaviour, strength properties and fracture features of theses adhesives were investigated by DSC, TMA, NAA, lap shear testing, tesile testing, lead pull testing, impact testing (NCMS drop test), optical microscopy and FESEM examination. Various cure techniques, adherend surfaces and loading methods were investigated to improve the adhesion and bulk strength of these ICAs.;The strength of ICA joints is determined to a small degree by cure conditions and surface chemistry and to a larger degree by the method of load application and geometry of the bond. The fracture behaviour of these composite materials is governed by macroscopic elastic and microscopic plastic effects. Silver deficient regions and voids are a significant problem that may limit widespread use of this material. Further problems include poor impact resistance, poor adhesion to Pb/Sn and unusual cure properties. |
