MANUFACTURE OF MEMBER WHOSE FORM OF SECTION VARIES IN LONDITUDINAL DIRECTION, MEMBER MADE BY THE MANUFACTURE, AND AIRPLANE MADE BY USING THE MEMBER

摘要

PROBLEM TO BE SOLVED: To manufacture at a low cost a member having a strength characteristics and a plastic workability equivalent to those of a member made by a cutout working by forming an integrated member by joining the side parts of an extended shape material and another extended shape material or a plate material, cutting one of the side parts so as to form a member whose form of section varies in a longitudinal direction of the joined member, and joining by a friction stirring joining. SOLUTION: A member 11 whose form of section varies in a manner that L-shaped ribs are arranged not parallely to each other is manufactured by diagonally cutting extended shape materials 5 having a uniform section at cutting lines 6 on side parts so that the member 11 forms a prescribed figure after joined, joining the extended shape materials 5 with a plate member 8 at their side parts along FSW joining lines 7 by a friction stirring welding. The integrated member after joined is worked by a plastic working to give a varied curvature, and the structure of the friction stirring welding zone acquires a strength similar to that of a base material when a solution heat treatment and an artificial aging process are given after the welding, thus a member equivalent to a member machined from a large plate material is provided at a lower cost. The member is applicable to a high strength member for an airplane or the like.