Solder for high temperature soldering and method of repairing and producing components using this solder

Solder (1) based on nickel, cobalt, or based on nickel-cobalt, comprises: a first metallic powder component (2) having particle sizes in the nanometer range; a second metallic powder component (3) having particle sizes in the micrometer range, where the surfaces of the particles of the second powder component are coated with particles of the first powder component; and at least one grain boundary stabilizing element as an alloying element of the first and of the second metallic powder components. Independent claims are also included for: (1) Repairing a component, which consists of single crystal or directionally solidified nickel-based, cobalt-based, or nickel-cobalt-based super-alloys as a base material and are damaged with at least one capillary crack, comprising introducing or applying the solder to the damaged region of the component, melting the solder by heat treating the component and cooling the component to room temperature, where an integral bond is formed between the solder and surrounding base material of the component, and a solidified solder is formed which has the same single crystal or directionally solidified microstructure as surrounding base material; (2) producing or repairing a modular component, preferably gas turbine blades, which have at least two component elements made of single crystal or directionally solidified nickel-based, cobalt-based, or nickel-cobalt-based super-alloys as a base material, where the component elements have surfaces, which lie face-to-face and are to be connected, comprising mechanically preparing the surfaces to be connected, applying the solder to at least one of the surfaces, joining the surfaces to one another with an exact fit, pressing the surfaces together to a capillary gap width, and melting the solder by heat treating, and cooling the melted solder to room temperature such that an integral bond between the solder and the surfaces of the component elements is formed; and (3) repairing the component, which consists of single crystal or directionally solidified nickel-based, cobalt-based, or nickel-cobalt-based super-alloy as base material, with a replacement piece (5) in the component to be repaired, where the replacement piece consists of a single crystal or directionally solidified nickel-based, cobalt-based, or nickel-cobalt-based super-alloy as base material, comprising mechanically preparing surfaces of the component and of the replacement piece which are to be connected, applying the solder in