Apparatus and process for joining homogeneous and heterogeneous materials with customized interface properties

摘要

An apparatus and method for improving friction spot welding process is described herein. According to the method of the present invention, two different metal sheets of similar or dissimilar material can be joined together with the help of a filler material that is filled in a cavity formed at the top of the upper metal sheet. Additionally, either a reinforcement material or an alloy element or combination of both is added in the cavity. The material is plasticized as the filler material is rotated and pushed in the cavity under the application of force. The weld is completed by filling the entire filler material at the weld interface. The addition of reinforcement material or an alloy element enables in customization of interface material properties enhancing the joint strength.

主权项

1. A method for joining of two or more weldable or non-weldable materials by using a friction stir spot welding, the method comprising steps of:
creating a cavity at a centre of overlapped welding surface of a first material and a second material by removing a portion of predefined geometry therefrom at least one of the first and the second materials to form a joint region; adding either reinforcement or an alloying element or combination of both into said created cavity in the joint region; penetrating a tapered cylindrical filler material with a similar geometry design as that of said cavity in the joint region by rotating said tapered cylindrical filler material in combination with compressive force thereto; interlocking the tapered cylindrical filler material with at least one of the first and second materials that is weldable with the filler material to form an inter-material bond; welding the first material with the second material by filling the cavity formed in the joint region with the tapered cylindrical filler material; and generating a composition structure at the weld interface with customized interface material properties.