Design of adhesive joints at cryogenic environment

A cryogenic containment system to prevent leakage of liquefied natural gas on carrier ships is composed of a primary barrier, insulation foam, and secondary barriers. Because the stainless steel metallic barriers in cryogenic containment systems must be joined together, the development of reliable joining technology at low temperatures or in harsh environments is important because the joint is generally the weakest part in the assembled structure. Epoxy resins are generally employed as the basis for adhesive components because they have many useful engineering properties, such as a high modulus, high failure strength, low creep, and good performance at elevated temperatures. However, epoxy resins are quite brittle, with poor resistance to crack initiation and propagation in cryogenic environments. Because of this, adhesives used in cryogenic systems need to be reinforced to increase their fracture toughness. In this study, we are developing the homogenous core–shell structured nanofibers with an epoxy matrix in the shell to achieve a substantial increase in the wettability, toughness, and mechanical properties of the adhesive at cryogenic temperature of −150 °C.

HJ Oh, SH Han, HY Kim, SS Kim. The influence of the core-shell structured meta-aramid/epoxy nanofiber mats on interfacial bonding strength and the mechanical properties of epoxy adhesives at cryogenic environment. Journal of Adhesion Science and Technology. 2014;28:950–962.

Electrospun nanofibers