Method of sealing a surface and device therefor

A method of sealing a surface to be sealed comprising:

• providing a metallic composition, the metallic composition consisting of a metal or a metal alloy;
• providing a propellant;
• heating the metallic composition to above the melting point of the metallic composition to provide at least partially liquid metallic composition;
• accelerating the at least partially liquid metallic composition towards the surface to be sealed by means of the propellant;
• applying the at least partially liquid metallic composition to the surface to be sealed,
• wherein the surface at least partially defines a volume defining a container, wherein the container comprises an at least partially liquid substance, and
• wherein the surface to be sealed comprises at least one surface defect to be sealed, the at least one surface defect is the source of an active leak from which matter comprising the at least partially liquid substance is escaping and the propellant provides sufficient propulsion to force the at least partially liquid metallic composition into the at least one surface defect and seal the surface defect when applying the at least partially liquid metallic composition to the surface.