Prefabricated houses are made up of separate pre-assembled modules that are joined to one another on-site – those modules, in turn, are made up of various wooden components that are typically nailed (or sometimes stapled) together in a factory. The wood used in the frames of the modules must be reasonably thick, in order not to split when the nails are driven in. This places some limitations on design possibilities. Now, however, German scientists have developed an alternative to those nails: electrically-activated adhesive tape.
Created by scientists at the Fraunhofer Institute for Wood Research and the Technische Universität Braunschweig, the tape actually consists of a thin strip of metal with adhesive on either side. As long as no electrical current is applied to the metal, the adhesive remains “unsticky.” This allows workers an indefinite amount of time in which to optimally place the tape and components together.
Once everything is ready to go, however, the tape gets zapped. This causes the metal to heat up, which subsequently causes the adhesive to melt and flow into the pores of the wood. Once the electrical current ceases, the adhesive cools and sets. The whole process only takes about one minute, and reportedly creates a durable bond.
By contrast, regular liquid adhesives used by some home manufacturers either take several hours to set, or require the whole module to be heated.
The researchers have already selected an adhesive that they say bonds well with both wood and metal. They are now looking into the merits of different types of metal including stainless steel, aluminum, and one of their current favorites, brass. They’re additionally working on shortening the amount of time required for bonding, and hope to test the tape in practical applications within about six months.