Abstract:
The welding can be carried out only after the partial removal of a necessary alitized portion prior to welding an alitized component.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to PCT Application No. PCT/EP2014/058064, having a filing date of Apr. 22, 2014, based off of European Application No. 13166930.1 having a filing date of May 8, 2013, the entire contents of which are hereby incorporated by reference. 
     
    
     FIELD OF TECHNOLOGY 
       [0002]    The following relates to the welding of alitized components and to an alitized component. 
       BACKGROUND 
       [0003]    Gas turbine components such as burner components have steels which are alitized in order to improve their corrosion properties. 
         [0004]    Hitherto, such components were not repaired. 
       SUMMARY 
       [0005]    An aspect relates to a method by means of which alitized components can be repaired or welded. 
         [0006]    By virtue of the method features and the component features, alitized components can be welded or have an advantageous weld. 
     
    
     
       BRIEF DESCRIPTION 
         [0007]    Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein: 
           [0008]      FIG. 1  shows schematically a sequence of an embodiment of a method and an embodiment of a component. 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    A substrate  4 , in particular made of a steel, very particularly made of 16Mo3, is to be welded or repaired. 
         [0010]    In that context, alitizing (+Al) is carried out in a first step, which produces a diffusion layer  6  within the substrate  4 , converting this into a modified substrate  4 ′, and generates a build-up layer  7 . 
         [0011]    Alitizing can also be carried out only locally. 
         [0012]    The diffusion layer  6  preferably has a depth of 150 μm to 300 μm. 
         [0013]    The build-up layer  7  preferably has a thickness of 100 μm. 
         [0014]    One part of the build-up layer  7  is in particular locally removed from the surface  13  of the diffusion layer  6  such that only a remnant  7 ′ of the build-up layer is present, wherein the build-up layer is largely, in particular entirely, removed with respect to its thickness and thus a surface  13  of the diffusion layer  6  forms an outer surface. The local removal of the build-up layer is expedient if only part of the alitized surface of the substrate  4 ′ is to be welded. 
         [0015]    In the next step, the exposed region  11  of the surface  13  is provided with a weld  10 . 
         [0016]    The procedure according to the prior art was to remove only the oxidized surface of aluminum of the build-up layer  7 . 
         [0017]    The removal of part of the build-up layer  7  can be carried out chemically and/or mechanically and/or by laser ablation. 
         [0018]    The weld  10  can be used to weld together burner components or to build up material in order to increase wall thickness. 
         [0019]    The repaired component has, next to one another, a substrate  4 ′ having a diffusion layer  6  and a weld  10  on the diffusion layer  6  together with a build-up layer  7 ′ on the surface  13  of the diffusion layer  6 .