Method for manufacturing heat exchanger plate and method for friction stir welding

Abstract

Certain embodiments relate to a heat exchanger plate capable of performing friction stir welding at a deep position of the heat exchanger plate, and improving air-tightness and water-tightness. A method may include a lid groove closing process to insert a lid plate into a lid groove formed at a periphery of a concave groove opening to a surface of a base member. The method may also include a primary joining process to perform friction stirring while relatively moving a primary joining rotary tool equipped with a stirring pin along a butting portion of a side wall of the lid groove and a side surface of the lid plate. In the primary joining process, the rotating stirring pin may be inserted into the butting portion, and the friction stirring may be performed in a state of only the stirring pin being in contact with the base member and the lid plate.

We claim: 
     
         1 . A method for manufacturing a heat exchanger plate, comprising:
 a closing process to overlay a lid plate on a front surface of a base member to cover a concave portion or a concave groove opening to the front surface of the base member;   a primary joining process to insert a rotary tool equipped with a stirring pin from a front surface of the lid plate, and to move the rotary tool along an overlapped portion of the front surface of the base member and a back surface of the lid plate; and   a deburring process to remove burrs generated by friction stirring using the rotary tool after finishing the primary joining process,   wherein the stirring pin has a tapered shape so as to have a smaller diameter in a hanging down direction and has a continuous spiral groove formed on an outer peripheral surface, the spiral groove configured to rotate in a counter-clockwise direction as it goes downward when the rotary tool is used for rotating in the clockwise direction, and the spiral groove is configured to rotate in the clockwise direction as it goes downward when the rotary tool is used for rotating in the counter-clockwise direction, and   wherein, in the primary joining process, friction stirring is performed to the overlapped portion with a base part of the stirring pin being exposed in a state of only the stirring pin of the rotary tool being in contact with both of the base member and the lid plate or with only the lid plate while plastically fluidized material does not flow into the concave portion or the concave groove.   
     
     
         2 . A method for manufacturing a heat exchanger plate, comprising:
 a closing process to overlay a lid plate on a front surface of a base member to cover a concave portion or a concave groove opening to the front surface of the base member;   a primary joining process to insert a rotary tool equipped with a stirring pin from a back surface of the base member, and to move the rotary tool along an overlapped portion of the front surface of the base member and a back surface of the lid plate; and   a deburring process to remove burrs generated by friction stirring using the rotary tool after finishing the primary joining process,   wherein the stirring pin has a tapered shape so as to have a smaller diameter in a hanging down direction and has a continuous spiral groove formed on an outer peripheral surface, the spiral groove configured to rotate in a counter-clockwise direction as it goes downward when the rotary tool is used for rotating in the clockwise direction, and the spiral groove is configured to rotate in the clockwise direction as it goes downward when the rotary tool is used for rotating in the counter-clockwise direction, and   wherein, in the primary joining process, friction stirring is performed to the overlapped portion with a base part of the stirring pin being exposed in a state of only the stirring pin of the rotary tool being in contact with both of the base member and the lid plate or with only the base member while plastically fluidized material does not flow into the concave portion or the concave groove.   
     
     
         3 . The method for manufacturing a heat exchanger plate according to  claim 1 , further comprising a preliminary joining process to preliminarily join the overlapped portion before the primary joining process. 
     
     
         4 . The method for manufacturing a heat exchanger plate according to  claim 2 , further comprising a preliminary joining process to preliminarily join the overlapped portion before the primary joining process. 
     
     
         5 . A method for friction stir welding to join two metal members with use of a rotary tool equipped with a stirring pin, comprising:
 an overlapped portion forming process to overlap a front surface of one metal member and a back surface of the other metal member to form an overlapped portion;   a primary joining process to move the rotary tool along the overlapped portion of the front surface of the one metal member and the back surface of the other metal member; and   a deburring process to remove burrs generated by friction stirring using the rotary tool after finishing the primary joining process,   wherein the stirring pin has a tapered shape so as to have a smaller diameter in a hanging down direction and has a continuous spiral groove formed on an outer peripheral surface, the spiral groove configured to rotate in a counter-clockwise direction as it goes downward when the rotary tool is used for rotating in the clockwise direction, and the spiral groove is configured to rotate in the clockwise direction as it goes downward when the rotary tool is used for rotating in the counter-clockwise direction,   wherein, in the primary joining process, friction stirring is performed to the overlapped portion with a base part of the stirring pin being exposed in a state of only the stirring pin of the rotary tool being in contact with both of the one metal member and the other metal member or with only the other metal member, and   wherein only a back surface of the one metal member contacts with a pedestal having a flat front surface larger than the back surface of the one metal member during the primary joining process.   
     
     
         6 . The method for friction stir welding according to  claim 5 , further comprising a preliminary joining process to preliminarily join the overlapped portion before the primary joining process.