Component Having Weld Seam and Method for Producing a Weld Seam

Abstract

During welding, frequently cracks develop at the end of the weld seam. A method is provided in which the power is reduced at the end of the weld seam, reducing the development of cracks. For the method, a welding appliance is used wherein the welding appliance may be a laser.

1 - 21 . (canceled) 
     
     
         22 . A component having a directionally solidified structure in the substrate, comprising:
 a weld seam,   wherein the weld seam extends at one end of the weld seam at least partially in a form of a ramp,   wherein the weld seam has a directionally solidified structure,   wherein the weld seam includes a length,   wherein the ramp includes a ramp length in a direction of the length of the weld seam, and   wherein the ramp length is considerably smaller than the length of the weld seam.   
     
     
         23 . The component as claimed in  claim 22 , wherein the weld seam extends at both ends in the form of a ramp. 
     
     
         24 . The component as claimed in  claim 22 ,
 wherein the weld seam includes a depth, and   wherein a ramp-shaped profile begins level with the depth of the weld seam.   
     
     
         25 . The component as claimed in  claim 24 , wherein the ramp-shaped profile does not extend up to a surface of the component. 
     
     
         26 . The component as claimed in  claim 24 , wherein the ramp-shaped profile extends up to a surface of the component. 
     
     
         27 . The component as claimed in  claim 22 , wherein the ramp length is 3 mm-7 mm. 
     
     
         28 . The component as claimed in  claim 22 , wherein the weld seam comprises the same material as the substrate. 
     
     
         29 . The component as claimed in  claim 22 , wherein the ramp of the weld seam includes a curved profile. 
     
     
         30 . A method for producing a weld seam with a length in a component, comprising:
 using a welding appliance; and   reducing a power of the welding appliance over a defined ramp length,   wherein the ramp length<1, at an end of the weld seam, and   wherein the component comprises:
 a weld seam, 
 wherein the weld seam extends at one end of the weld seam at least partially in a form of a ramp, 
 wherein the weld seam has a directionally solidified structure, 
 wherein the weld seam includes a length, 
 wherein the ramp includes a ramp length in a direction of the length of the weld seam, and 
 wherein the ramp length is considerably smaller than the length of the weld seam. 
   
     
     
         31 . The method as claimed in  claim 30 , wherein the welding appliance used is a laser. 
     
     
         32 . The method as claimed in  claim 30 , wherein the power of the welding appliance is reduced to 0 watt at one end of the weld seam. 
     
     
         33 . The method as claimed in  claim 30 , wherein the power of the welding appliance is not reduced to 0 watt at the end of the weld seam. 
     
     
         34 . The method as claimed in  claim 30 , wherein the power of the welding appliance is reduced at the end of the weld seam within 4 s to 8 s. 
     
     
         35 . The method as claimed in  claim 30 , wherein a preheating temperature of the substrate is controlled and/or regulated. 
     
     
         36 . The method as claimed in  claim 30 , wherein a travel speed during a ramp formation is 40 mm/min-60 mm/min. 
     
     
         37 . The method as claimed in  claim 30 , wherein the power of the welding appliance is increased over the defined ramp length, where the ramp length<1, at the start of the weld seam. 
     
     
         38 . The method as claimed in  claim 30 , wherein the power of the welding appliance is increased or decreased linearly during the production of the ramp. 
     
     
         39 . The method as claimed in  claim 30 , wherein the substrate of the component includes a directionally solidified structure. 
     
     
         40 . The method as claimed in  claim 30 , wherein a melt front produced by the welding appliance remains further in forward motion up to the end of the weld seam or until the welding appliance is switched off 
     
     
         41 . The method as claimed in  claim 30 , wherein the relative movement between the substrate and the welding appliance is maintained until the welding appliance is switched off.