To provide a method for friction stir welding a stainless steel panel to an extruded aluminum alloy shape member.
A side structure 2 of a car body 1 is formed by friction stir welding aluminum alloy extruded hollow shape members 30, 40 from the inner side of the car. On the outer side of the side structure 2, stainless steel panels 10, 20 are welded by the friction stir welding to the butted portion between hollow shape members 30, 40 from the inner side of the car. After friction stir welding the butted portion between the hollow shape members 30, 40, inner face plates 31, 41 of the hollow shape members 30, 40 are connected via a connecting member 51. According to the present method, scratches on the surface of the car body can be reduced by arranging the stainless steel panels 10, 20 on the outer side of the car. Except parts of the stainless steel panels 10, 20, the structure is made of aluminum alloy and can be manufactured in light weight and at low cost. Also, between the stainless steel panels and between the hollow shape members, friction stir welding is performed by abutting or overlapping them on each other. It is possible to arrange heat insulation members between the stainless steel panels and the hollow shape members.
TOTORI SEIJIROU
OKADA TOMONORI
SAGAWA TOSHIAKI
