A method of mechanically securing a first object to a second object, wherein the first object has a thermoplastic material in a solid state, the second object has a generally flat sheet portion having a second object edge. A third object is provided and arranged to provide an assembly including the first, second and third objects, in which assembly the second object edge is in contact with the thermoplastic material. Mechanical vibration energy is coupled into the assembly by means of a vibrating tool until a flow portion of the thermoplastic material due to friction heat generated between the second object edge and the thermoplastic material becomes flowable and flows around the second object edge to at least partially embed the second object edge in the thermoplastic material and the third object is caused to be embedded at least partially in the thermoplastic material of the first object.

The invention relates to a friction stir welding device for producing a spot-shaped or linear weld joint between a plastic plate or a plastic moulding and a metal or plastic substrate, comprising a welding head and a manually operable or controlled linear feed for the linear movement of the welding head, wherein the welding head comprises a rotatable or oscillatable stirring pin and an outer sleeve surrounding the stirring pin, wherein there is provided a reservoir for receiving material displaced by the stirring pin between the outer sleeve and the stirring pin, wherein the reservoir is limited by a step formed integrally with the outer sleeve or by a reservoir sleeve provided between the outer sleeve and the stirring pin.

A tool presses a joining element against a first object into a first opening of the first object while mechanical vibration energy is coupled into the first object and the joining element. Vibration energy and pressing force make the thermoplastic material of the distal portion of the joining element flowable and interpenetrates structures of the first object to yield, after re-solidification, an anchoring of the distal portion of the joining element in the first object. The second object is placed so that a proximal portion of the joining element is inserted into a second opening, and the first and second objects are pressed against each other while mechanical vibration energy is coupled into one of the first and second objects, until thermoplastic material of the joining element proximal portion is made flowable and interpenetrates structures of the second object to yield, after re-solidification, an anchoring in the second object.

A process, apparatus and a catheter and a flexi needle for medical applications formed by the process of selecting a tubular flexible member and a metal/ceramic cap member to be securely joined to the tubular member, placing the cap member in engaging relation with a holding member of a material joining device, securing the tubular member on a positioning member of the material joining device, positioning a distal end of the tubular member in engaging relation with an end of the cap member positioned in the holding member, and rotating the holding member and maintaining the tubular member in frictionally engaging relation with the cap member to melt or soften a predetermined portion of the distal end of the tubular member engaged with the cap member to integrally join a predetermined portion of the distal end of the tubular member within the cap member forming a joined composite member.