Design and ageing of adhesives for structural adhesive bonding – A review

Abstract

This review outlines some of the issues which have to be addressed when selecting an adhesive for a particular structural adhesive bonding application. The designer may find that a number of adhesives provide the required load bearing properties and the selection may require a more detailed consideration of the processes involved in the fabrication of the joint, the temperature over which it is to work and the environment in which it will have to operate. The article attempts to provide the reader with an insight into the effects of factors such as time and temperature used in the cure process, details of the components in the mixture and the effects of various additives on the physical properties of the adhesives which are created. The performance of an adhesive may vary with time as a consequence of stress-induced changes which are triggered by thermal effects or by hygrothermal factors. The review considers joints created using metal substrates and carbon fibre composites. The performance and durability of an adhesive bond is critically dependent on the stability of the interface between the adhesive and adherend and is sensitive to the pre-treatment processes used in the creation of the bond. The review outlines how broadband dielectric measurements can be used to non-destructively monitor the cure of adhesive bonds and the processes involved in ageing of joint. The dielectric method gives an insight into the fundamental processes which are giving rise to the changes in the mechanical properties of the joint as they age.

Bor Nitrür Nanoplateletlerin ve Nano Ag Takviyeli Yapısal Yapıştırıcıların Kayma Dayanımı

“…Epoksiler, uçak parçaları, borulardaki korozyon önleyici kaplamalar ve elektronik aygıtlar gibi yapıştırıcı olarak birçok mühendislik uygulamasında yaygın olarak kullanılmıştır [3]. Ancak epoksilerin düşük dayanımları ve toklukları, birçok durumlarda kullanımlarını sınırlamaktadır.…”

The Effect of Ageing in Water Solution Containing Iron Sulfate on the Mechanical Properties of Epoxy Adhesives

“…Another advantage of adhesives is their vibration damping capability, a feature that is extremely desired in industries such as automotive or aircraft. What is more, it is possible to bond two completely different adherends, and no electrochemical corrosion will occur because the adhesive acts as an insulator for bonded elements [2][3][4]6].…”

“…Liechti et al [28] presented that, in the air and in salt water, raising the temperature reduced the threshold energy release rate, and this decrease was more in salt water than in air. The results of the effects of environmental factors on the long-term performance of adhesive joints depicted in the works prepared by Pethrick [6], Heshmati et al [16] and Karbhari et al [5] underlined that moisture (in the form of humidity), liquid water or de-icing salt solutions are the most damaging substances. Bellini et al [14] investigated the combined effect of hydrothermal ageing and the temperature test on the lap shear strength of single lap joints that are realized in CFRP (carbon fiber reinforced polymer).…”

The Effect of the Salt Water Aging on the Mechanical Properties of Epoxy Adhesives Compounds

“…In liquid form, they can be used for joining elements made of different materials. When subjected to curing, however, these materials form solid, resistant structures with low specific weight, which show different properties in various environments [5][6][7][8][9], including water [10][11][12][13], moisture [14][15][16], humid [17][18][19] or hydrothermal conditions [20].…”