A seal includes an elastomeric material and a plurality of nanosprings filling the elastomeric material to form a filled elastomeric composite that provides the seal. A spring constant of the nanosprings is within a selected range of an effective spring constant of the elastomeric material such that a durometer of the filled elastomeric composite at an elevated temperature is greater than the durometer of the elastomeric material alone at the elevated temperature. The seal may be used to seal a first component to a second component where both components are configured to perform a task below the surface of the earth.