Apparatus and method for friction stir welding using a consumable pin tool

Abstract

The present invention provides a friction stir welding apparatus operable for welding one or more metals, metal alloys, or other materials. The friction stir welding apparatus includes a pin tool holder, a shoulder having a surface coupled to the pin tool holder, and a pin tool coupled to the pin tool holder, the pin tool at least partially protruding from the surface of the shoulder, wherein the pin tool is made of a consumable pin tool material. Optionally, the shoulder rotates at a predetermined rotational speed and is retractable into/extendable from the pin tool holder at a substantially constant rate. Optionally, the shoulder is also made of a consumable shoulder material that is at least partially incorporated into the volume of a joint to be welded. The consumable shoulder material comprises a material that is the same as, similar to, or dissimilar from one or more materials comprising a workpiece to be friction stir welded. Preferably, the pin tool rotates at a predetermined rotational speed and is retractable into/extendable from the surface of the shoulder at a substantially constant rate. The consumable pin tool material is at least partially incorporated into the volume of the joint to be welded. The consumable pin tool material comprises a material that is the same as, similar to, or dissimilar from one or more materials comprising the workpiece to be friction stir welded.

1 . A friction stir welding apparatus operable for welding one or more metals, metal alloys, or other materials, the friction stir welding apparatus comprising: 
 a pin tool holder;    a shoulder having a surface and an inside diameter; and    a pin tool coupled to the pin tool holder, the pin tool at least partially disposed within the inside diameter of the shoulder and at least partially protruding from the surface of the shoulder, wherein the pin tool comprises a consumable pin tool material.    
   
   
       2 . The friction stir welding apparatus of  claim 1 , wherein the shoulder rotates at a predetermined rotational speed.  
   
   
       3 . The friction stir welding apparatus of  claim 1 , wherein the shoulder is retractable into/extendable from the pin tool holder.  
   
   
       4 . The friction stir welding apparatus of  claim 3 , wherein the shoulder is retractable into/extendable from the pin tool holder at a substantially constant rate.  
   
   
       5 . The friction stir welding apparatus of  claim 1 , wherein the shoulder comprises a consumable shoulder material.  
   
   
       6 . The friction stir welding apparatus of  claim 5 , wherein the consumable shoulder material is at least partially incorporated into the volume of a joint to be welded.  
   
   
       7 . The friction stir welding apparatus of  claim 5 , wherein the consumable shoulder material comprises a material that is the same as one or more materials comprising a workpiece to be friction stir welded.  
   
   
       8 . The friction stir welding apparatus of  claim 5 , wherein the consumable shoulder material comprises a material that is similar to one or more materials comprising a workpiece to be friction stir welded.  
   
   
       9 . The friction stir welding apparatus of  claim 5 , wherein the consumable shoulder material comprises a material that is dissimilar from one or more materials comprising a workpiece to be friction stir welded.  
   
   
       10 . The friction stir welding apparatus of  claim 1 , wherein the pin tool rotates at a predetermined rotational speed.  
   
   
       11 . The friction stir welding apparatus of  claim 1 , wherein the pin tool is retractable into/extendable from the surface of the shoulder.  
   
   
       12 . The friction stir welding apparatus of  claim 11 , wherein the pin tool is retractable into/extendable from the surface of the shoulder at a substantially constant rate.  
   
   
       13 . The friction stir welding apparatus of  claim 1 , wherein the consumable pin tool material is at least partially incorporated into the volume of a joint to be welded.  
   
   
       14 . The friction stir welding apparatus of  claim 1 , wherein the consumable pin tool material comprises a material that is the same as one or more materials comprising a workpiece to be friction stir welded.  
   
   
       15 . The friction stir welding apparatus of  claim 1 , wherein the consumable pin tool material comprises a material that is similar to one or more materials comprising a workpiece to be friction stir welded.  
   
   
       16 . The friction stir welding apparatus of  claim 1 , wherein the consumable pin tool material comprises a material that is dissimilar from one or more materials comprising a workpiece to be friction stir welded.  
   
   
       17 . The friction stir welding apparatus of  claim 1 , wherein the shoulder has a substantially cylindrical shape.  
   
   
       18 . The friction stir welding apparatus of  claim 1 , wherein the pin tool has a shape selected from the group consisting of substantially cylindrical, substantially rod-like, and substantially conical.  
   
   
       19 . The friction stir welding apparatus of  claim 1 , wherein the pin tool has a substantially tapered shape comprising a tip radius.  
   
   
       20 . The friction stir welding apparatus of  claim 1 , further comprising a first axial load feedback controller coupled to the shoulder, the first axial load feedback controller operable for controlling a feed rate of the shoulder.  
   
   
       21 . The friction stir welding apparatus of  claim 20 , further comprising a second axial load feedback controller coupled to the pin tool, the second axial load feedback controller operable for controlling a feed rate of the pin tool.  
   
   
       22 . The friction stir welding apparatus of  claim 21 , wherein the second axial load feedback controller comprises the first axial load feedback controller.  
   
   
       23 . The friction stir welding apparatus of  claim 21 , wherein the feed rate of the shoulder is equal to the feed rate of the pin tool.  
   
   
       24 . A friction stir welding apparatus operable for welding one or more metals, metal alloys, or other materials, the friction stir welding apparatus comprising: 
 a pin tool holder;    a shoulder having a surface and an inside diameter; and    a pin tool coupled to the pin tool holder, the pin tool at least partially disposed within the inside diameter of the shoulder and at least partially protruding from the surface of the shoulder, wherein the pin tool is retractable into/extendable from the surface of the shoulder, and wherein the pin tool rotates at a first predetermined rotational speed, and wherein the pin tool further comprises a consumable pin tool material.    
   
   
       25 . The friction stir welding apparatus of  claim 24 , wherein the shoulder rotates at a second predetermined rotational speed.  
   
   
       26 . The friction stir welding apparatus of  claim 24 , wherein the shoulder is retractable into/extendable from the pin tool holder.  
   
   
       27 . The friction stir welding apparatus of  claim 26 , wherein the shoulder is retractable into/extendable from the pin tool holder at a substantially constant rate.  
   
   
       28 . The friction stir welding apparatus of  claim 24 , wherein the shoulder comprises a consumable shoulder material.  
   
   
       29 . The friction stir welding apparatus of  claim 28 , wherein the consumable shoulder material is at least partially incorporated into the volume of a joint to be welded.  
   
   
       30 . The friction stir welding apparatus of  claim 28 , wherein the consumable shoulder material comprises a material that is the same as one or more materials comprising a workpiece to be friction stir welded.  
   
   
       31 . The friction stir welding apparatus of  claim 28 , wherein the consumable shoulder material comprises a material that is similar to one or more materials comprising a workpiece to be friction stir welded.  
   
   
       32 . The friction stir welding apparatus of  claim 28 , wherein the consumable shoulder material comprises a material that is dissimilar from one or more materials comprising a workpiece to be friction stir welded.  
   
   
       33 . The friction stir welding apparatus of  claim 24 , wherein the pin tool is retractable into/extendable from the surface of the shoulder at a substantially constant rate.  
   
   
       34 . The friction stir welding apparatus of  claim 24 , wherein the consumable pin tool material is at least partially incorporated into the volume of a joint to be welded.  
   
   
       35 . The friction stir welding apparatus of  claim 24 , wherein the consumable pin tool material comprises a material that is the same as one or more materials comprising a workpiece to be friction stir welded.  
   
   
       36 . The friction stir welding apparatus of  claim 24 , wherein the consumable pin tool material comprises a material that is similar to one or more materials comprising a workpiece to be friction stir welded.  
   
   
       37 . The friction stir welding apparatus of  claim 24 , wherein the consumable pin tool material comprises a material that is dissimilar from one or more materials comprising a workpiece to be friction stir welded.  
   
   
       38 . The friction stir welding apparatus of  claim 24 , wherein the shoulder has a substantially cylindrical shape.  
   
   
       39 . The friction stir welding apparatus of  claim 24 , wherein the pin tool has a shape selected from the group consisting of substantially cylindrical, substantially rod-like, and substantially conical.  
   
   
       40 . The friction stir welding apparatus of  claim 24 , wherein the pin tool has a substantially tapered shape comprising a tip radius.  
   
   
       41 . The friction stir welding apparatus of  claim 24 , further comprising a first axial load feedback controller coupled to the shoulder, the first axial load feedback controller operable for controlling a feed rate of the shoulder.  
   
   
       42 . The friction stir welding apparatus of  claim 41 , further comprising a second axial load feedback controller coupled to the pin tool, the second axial load feedback controller operable for controlling a feed rate of the pin tool.  
   
   
       43 . The friction stir welding apparatus of  claim 42 , wherein the second axial load feedback controller comprises the first axial load feedback controller.  
   
   
       44 . The friction stir welding apparatus of  claim 42 , wherein the feed rate of the shoulder is equal to the feed rate of the pin tool.  
   
   
       45 . A method for friction stir welding one or more metals, metal alloys, or other materials, the method comprising: 
 providing a pin tool holder;    providing a shoulder having a surface and an inside diameter;    providing a pin tool coupled to the pin tool holder, the pin tool at least partially disposed within the inside diameter of the shoulder and at least partially protruding from the surface of the shoulder, wherein the pin tool comprises a consumable pin tool material; and    incorporating at least a portion of the consumable pin tool material into the volume of a joint to be welded.    
   
   
       46 . The method of  claim 45 , wherein providing the shoulder further comprises rotating the shoulder at a predetermined rotational speed.  
   
   
       47 . The method of  claim 45 , wherein providing the shoulder further comprises retracting the shoulder into/extending the shoulder from the pin tool holder.  
   
   
       48 . The method of  claim 47 , wherein providing the shoulder further comprises retracting the shoulder into/extending the shoulder from the pin tool holder at a substantially constant rate.  
   
   
       49 . The method of  claim 45 , wherein the shoulder comprises a consumable shoulder material.  
   
   
       50 . The method of  claim 49 , further comprising incorporating at least a portion of the consumable shoulder material into the volume of the joint to be welded.  
   
   
       51 . The method of  claim 49 , wherein the consumable shoulder material comprises a material that is the same as one or more materials comprising a workpiece to be friction stir welded.  
   
   
       52 . The method of  claim 49 , wherein the consumable shoulder material comprises a material that is similar to one or more materials comprising a workpiece to be friction stir welded.  
   
   
       53 . The method of  claim 49 , wherein the consumable shoulder material comprises a material that is dissimilar from one or more materials comprising a workpiece to be friction stir welded.  
   
   
       54 . The method of  claim 45 , wherein providing the pin tool further comprises rotating the pin tool at a predetermined rotational speed.  
   
   
       55 . The method of  claim 45 , wherein providing the pin tool further comprises retracting the pin tool into/extending the pin tool from the surface of the shoulder.  
   
   
       56 . The method of  claim 55 , wherein providing the pin tool further comprises retracting the pin tool into/extending the pin tool from the surface of the shoulder at a substantially constant rate.  
   
   
       57 . The method of  claim 45 , wherein the consumable pin tool material comprises a material that is the same as one or more materials comprising a workpiece to be friction stir welded.  
   
   
       58 . The method of  claim 45 , wherein the consumable pin tool material comprises a material that is similar to one or more materials comprising a workpiece to be friction stir welded.  
   
   
       59 . The method of  claim 45 , wherein the consumable pin tool material comprises a material that is dissimilar from one or more materials comprising a workpiece to be friction stir welded.  
   
   
       60 . The method of  claim 45 , wherein the shoulder has a substantially cylindrical shape.  
   
   
       61 . The method of  claim 45 , wherein the pin tool has a shape selected from the group consisting of substantially cylindrical, substantially rod-like, and substantially conical.  
   
   
       62 . The method of  claim 45 , wherein the pin tool has a substantially tapered shape comprising a tip radius.  
   
   
       63 . The method of  claim 45 , further comprising receiving a first axial load feedback from the shoulder and controlling a feed rate of the shoulder based on the first axial load feedback.  
   
   
       64 . The method of  claim 63 , further comprising receiving a second axial load feedback from the pin tool and controlling a feed rate of the pin tool based on the second axial load feedback.  
   
   
       65 . The method of  claim 64 , wherein the second axial load feedback comprises the axial load feedback.  
   
   
       66 . The method of  claim 64 , wherein the feed rate of the shoulder is equal to the feed of the pin tool.