Annular barrier

An annular barrier for expansion in an annulus between a first well tubular metal structure and an inner face of a borehole or a second well tubular metal structure for providing zone isolation between a first zone and a second zone of the annulus, the annular barrier having a first axial extension, where the annular barrier comprises:

• a tubular metal part for mounting as part of the first well tubular metal structure, the tubular metal part having an outer face,
• an expandable metal sleeve surrounding the tubular metal part and having an outer face facing towards the inner face of the borehole or the second well tubular metal structure and an inner face facing the outer face of the tubular metal part, a second axial extension along the first axial extension, and each end of the expandable metal sleeve being connected with the tubular metal part,
• an annular space between the expandable metal sleeve and the tubular metal part,
• an expansion opening in the tubular metal part through which fluid may enter the annular space in order to expand the expandable metal sleeve,
• a eutectic material and/or a bentonite material which in a first condition is arranged on the outer face of the tubular metal part in a first axial position different from the second axial extension of the expandable metal sleeve, and in a second condition and a second axial position the eutectic material and/or the bentonite material abuts a face of the expandable metal sleeve, and in an intermediate condition the eutectic material and/or the bentonite material is positioned between the first axial position and the second axial position, and
• a fluid communication channel extending from a position facing the outer face of the tubular metal part and having a first opening in a first axial channel position, and the fluid communication channel extending towards a second opening in a second axial channel position, where the second axial channel position overlaps or abuts an axial position of the expandable metal sleeve, and in the first condition the eutectic material is arranged upstream to the first opening, and in the second condition the eutectic material abuts the face of the expandable metal sleeve downstream to the second opening.