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74 PCB007 MAGAZINE I NOVEMBER 2021 In the October 2019 edi- tion of PCB007 Maga- zine 1 , Victor Lazaro Gal- lego explained, "e nov- elty of this new technol- ogy, however, is that the thermal energy (heat) to cure the resin compos- ites is produced directly at each of the stainless-steel separator plates that are between each multilayer panel in the press stacks. is thermal energy is transferred at the same time—with the same tem- perature magnitude and without any thermal con- duction delays—to every panel of the lamination press stack. As the energy is induced very homogenously, the heat distri- bution has the highest uniformity possible in every position and direction of the press stack (X-, Y-, and Z-axes). erefore, all the layers of laminates inside the press reach the same tem- perature at the same time; there are no thermal transfer delays. Because the heat is produced only at each stainless-steel separator plate of the stack, the technology can achieve extremely high temperatures and very rapid ramp-up rates with very high energy efficiency." Principle of Operation Electromagnetism is generated when an electric current move through an electrical coil, as is defined by the Biot-Savart Law 2 . A magnetic field generated on the inside of the coil and looping around the coil perpendicular to the current in the coil is associated with the electric current in the coil. is phenomenon also works in reverse. When a magnetic field is created by an elec- tric current moving in a coil, an electric cur- rent can be made to flow and can induce elec- tric currents in a secondary coil, if the mag- netic field is placed in proper alignment to the primary coil. For a multilayer stackup, the properly aligned stainless-steel caul-plate is working as a one turn coil in a short circuit for the induced cur- rents (Figure 2). e induced magnetic field converts such energy on each stainless-steel separator plate (induced electric energy) into thermal energy (heat) by the eddy current loss theory 3 . Saving Energy, Time, and Money Not having hot, massive platens to heat up and be maintained at high temperatures means that the energy usage is going to be minimized (reported to be ~10% of a hot press) and insulation materials will not be not required, since the separator plates them- selves are the source of heat. A dummy panel with the same materials and physical proper- ties as the laminate is embedded with a tem- perature sensor to track the temperature of the stack in real-time (Figure 3). To better illustrate the efficiency of this new technology, Chemplate took thermogra- Figure 2: Stainless steel press stack separation plates as the secondary coil to induce heat. (Source: Chemplate)