Patent Number: 
Section: claims

1. A container for radioactive materials comprising a main hollow body as well as a cover made of at least a first metallic material, said cover being fixed on the main hollow body by means of sealing means made of a second metallic material poured into a groove defined by the cover and the main hollow body of the container, wherein the cover and the main hollow body are made solid with said sealing means by means of a bonding zone, formed by chemical reaction between the first and second metallic materials, wherein the first metallic material comprises a material selected from the group consisting of cast iron and steel, and wherein the second metallic material poured is a material selected from the group consisting of aluminum and aluminum alloys, with the bonding zone being composed of an iron-aluminum alloy. 2. A container for radioactive materials comprising a main hollow body as well as a cover made of at least a first metallic material, said cover being fixed on the main hollow body by means of sealing means made of a second metallic material poured into a groove defined by the cover and the main hollow body of the container, wherein the cover and the main hollow body are made solid with said sealing means by means of a bonding zone, formed by chemical reaction between the first and second metallic materials, and wherein the bonding zone uses an average thickness of between 10 mm and 5 mm. 3. The container as claimed in claim 1 or claim 2, in which the cover comprises an external lateral surface partially defining said groove and comprising two adjacent portions inclined respectively at an angle α and an angle β relative to a direction parallel to a longitudinal principal axis of the container, the angles a and β being acute and opposite so a to produce a corner effect. 4. A process for closing a container for radioactive materials comprising a main hollow body as well as a cover made of at least a first metallic material, said process comprising a stage of placing the cover on said main hollow body of the container so as to form a groove between these two elements, followed by a stage of excess pouring the second metallic material in said groove over a determined period, so as to cause heating of the first metallic material constituting said groove as well as washing the surfaces of this groove, followed by a stage of making sealing means ensuring fixing of the cover onto the main hollow body of the container by pouring a second metallic material into said groove wherein the second metallic material is selected such that it reacts chemically with each first metallic material, so as to form a bonding zone between the sealing means on the one hand, and the cover and the main hollow body of the container on the other hand. 5. The process as claimed in claim 4, in which the stage of placing the cover is followed by a stage of pre-heating the first material constituting the groove. 6. The process as claimed in claim 5, in which the stage of pre-heating is preceded by a preparation stage of the surfaces of the groove. 7. The process as claimed in claim 6, in which the preparation stage of the surfaces of the groove is done by means of at least one preparation technique taken from the group constituted by mechanical, chemical and electrochemical techniques for preparation of surfaces, and techniques for depositing layers of metallic materials. 8. The process as claimed in claim 4, in which the stage of making the sealing means by pouring the second metallic material into said groove is followed by a heating stage of this second material resting in said groove, so as to favor chemical reaction between the first and second metallic materials.