| 摘要 |
<p>A method of bonding areas of two elements of a sheet molded compound to form a bonded product includes intimate mixing of a thermoset epoxy or polyurethane adhesive with submicron particles selected from the group of gamma Fe2O3 and magnetic iron oxide Fe3O4, with the particles typically being 5 to 40% by weight of the final adhesive mixture to form a semi-liquid adhesive mixture. A bead of the adhesive mixture is located between the elements to be joined, and the elements are forced toward each other to compress and spread the semi-liquid adhesive mixture to form a flattened bonding element in intimate contact with the surfaces to be joined with an accurately controlled typical thickness of the adhesive of 0.005 inches to 0.2 inches. An induction coil is coupled to the elements and energized with a high frequency current of a frequency of from 1.5 to 8 MHz for a total period of about thirty seconds. The current level and time is controlled to first rapidly heat the adhesive without significant heating of the elements, and after the cure temperature is reached to reduce the power input and hold an optimum heat level for a sufficient time to create a gel condition. The bonded product is then transferred for further working.</p> |
