At least two materials are superposed and a rotary tool 1 is pressed on a first material W 1 at an outermost surface, whereby metal texture between the superposed first and second materials W 1 , W 2 is agitated by frictional heat in a melting condition to join the materials.

Method and apparatus for joining

A friction stir welding machine includes a table for supporting parts to be welded and a frame extending over the table. A first drive is supported by a first element of the frame and is operatively connected to a spindle having a tool. The first drive moves the tool in a first direction, and the first drive disengages from the spindle after the tool contacts the material. A second drive is supported by a second element of the frame and is operatively connected to the spindle for moving the tool into the parts at a joint, thereby initiating friction stir welding process. The friction stir welding machine has a pair of rollers mounted in a roller support with an axis of rotation substantially perpendicular to an axis of rotation of the tool. The rollers contact a surface of the material in response to the tool penetrating the material to a desired depth. The roller support is pivotally mounted to the spindle and has a pivot axis substantially perpendicular to both an axis of rotation of the rollers and the axis of rotation of the tool. The work supporting table of the friction stir welding machine has a vacuum hold down system for securing the parts to the table.

Friction stir welding machine and method

An apparatus and method for forming a friction stir weld joint in a workpiece are provided. The apparatus includes a friction stir welding tool having a shoulder and a rotatable pin extending therefrom. The rotational speed of the pin can be adjusted during a friction stir welding operation, e.g., cyclically and/or according to a predetermined schedule, so that the pin mixes the plasticized material of the workpiece. The workpiece can also be preheated before friction stir welding.

Apparatus and method for friction stir welding with a variable speed pin

In this invention, a tool drive unit (53) of a friction stir spot welding device is configured to move a pin member (11) and a shoulder member (12) forward and backward, and is controlled by a tool drive control unit (21). A press-fit reference point setting unit (22) sets the position of the pin member (11) or the shoulder member (12) when contacting an object to be welded (60) as the press-fit reference point. The tool drive control unit (21) controls the press-fit depth when a rotating tool (51) press-fits the object to be welded (60) starting at the surface thereof by controlling the relative location of the pin member (11) in relation to the shoulder member (12) based on the press-fit reference point. Thus, good welding quality with suitable precision in accordance with welding conditions can be achieved, especially with a double-acting type friction stir spot welding method.

Friction stir spot welding device and friction stir spot welding method

A spot joining device comprises a joining tool, an induction motor for rotating the joining tool, a servo motor for vertically moving the joining tool along an axis of the joining tool, and a receiving member placed opposite to the joining tool. The joining tool includes a short-column shaped shoulder and a pin protruded downwardly along the axis from a central portion of a lower face of the shoulder at a tip end portion thereof. Two works such as aluminum alloy plates are lapped and placed on a receiving member. When the joining tool is rotated and moved downwardly, a joint spot of the works is heated and softened due to friction heat generated by the rotating pin. Thereby, plastic flow occurs in the vicinity of the joint spot. The vicinity of the joint spot is stirred and the works are fused at the joint spot. Thus, the works are spot-joined.

Spot joining method and spot joining device

Modified method for friction stir welding process where the shoulder (2) being independently movable of the pin (1) exercises controlled and variable forces on the assembled joined-to-be members so that the down force under retraction of the pin exceeds the plasticity limit of excess material collected under the shoulder.

Jan Charles Bersaas

Papers

Friction stir spot welding method and apparatus