Fabricated-in-place inserts to receive self-piercing rivets

A method of joining, with a self-piercing rivet, a first article to a second article;

• each of the first and second articles having one or more joining regions and each joining region on each article having two opposed joining surfaces, a first surface and a second surface;
• the first article comprising a cast metal or reinforced molded polymer material of limited ductility, the first article being susceptible to damage prejudicial to joint strength when penetrated by a self piercing rivet, the first article having, at each joining region, a ductile sheet metal insert in secure, interlocked engagement with the first article, the insert being suitable for receiving a self piercing rivet;
• each sheet metal insert having exposed, opposed surfaces, the exposed surfaces of each sheet metal insert being the joining surfaces of the first article;
• the self-piercing rivet having a hollow cylindrical body with a length, a closed end, an open end, and an outside diameter;
• the closed end of the rivet being closed with a cap having a larger diameter than the diameter of the body, the cap having a top side and an underside, the method comprising:
• placing the first surface of a selected insert in the first article in contacting, face-to-face relation with the first joining surface of a predetermined joining region of the second article;
• placing an upstanding self piercing rivet on either of the second insert surface or the second joining surface of the second article, the open end of the rivet being in contact with the insert or the joining surface of the second article;
• applying pressure to the top side of the cap of the upstanding self piercing rivet sufficient to drive the open end of the rivet into the second surface of the insert or into the second surface of the second article while supporting the second surface of either the second article or the second surface of the insert with a shaped die, so that the rivet is driven through one of the second article or the insert and into the insert or into the second article and the underside of the rivet cap is driven into engagement with the underlying second surface of one of the article or insert;
• and
• the open end of the rivet is radially expanded by action of the shaped die to secure the insert to the second article and thereby join the first article to the second article.