Patent ID: 8157943
Filing Date: 2012-04-17
Classification: B21D,B23K,Y10T

Abstract:
1. A method for producing a hemmed joint structure having a second member made of an iron-based material placed on a first member made of an aluminum-based material, and an edge portion of the first member bent over the second member to join the two members with each other, the method comprising the steps of: providing a flange part jutting out from part of an edge of the first member, the first member having an edge portion provided with the flange part; applying a room-temperature-curing adhesive to the first member continuously along the edge portion of the first member such that the applied adhesive forms a continuous adhesive layer extending parallel to the edge portion of the first member and separated by the edge portion of the first member from the flange part; placing an edge portion of the second member on the adhesive layer and allowing the adhesive to cure at room temperature, thereby adhesively bonding the edge portion of the second member to the first member using the adhesive layer of the room-temperature-curing adhesive; bending the edge of the first member over the adhesively bonded edge portion of the second member such that the flange part of the first member does not overlap the adhesive layer; fusion-bonding the flange part to the second member by friction stir bonding while the adhesive layer is maintained without damage due to friction heat produced during the friction stir bonding, wherein a recess is formed in an upper side of the flange part; and applying a sealant to a gap between a front edge of the bent first member and the second member as well as to the upper side of the flange part to fill the recess.