A joint between one or more structural members and an associated method are provided. The joint includes a friction weld joint or other connection between faying surfaces of the members, and an exothermically reacted sealant disposed in an interface defined by the faying surfaces. The exothermic reaction of the sealant in the interface can be initiated before, during, or after joining the structural members such that the sealant at least partially seals the interface. The sealant can fill the spaces between the structural members to prevent the entry of chemicals, moisture, debris, and other substances, thereby reducing the likelihood of corrosion of the joint or structural members at the interface. Further, the sealant can form a bond with the structural members, thereby increasing the strength of the connection between the members.