Usefulness of Foundry Tooling Materials in Microwave Heating Process

Abstract

The paper describes preliminary examinations on establishing usefulness criteria of foundry tooling materials in the microwave heating technology. Presented are measurement results of permittivity and loss tangent that determine behaviour of the materials in electromagnetic field. The measurements were carried-out in a waveguide resonant cavity that permits precise determination the above-mentioned parameters by perturbation technique. Examined were five different materials designed for use in foundry tooling. Determined was the loss factor that permits evaluating usefulness of materials in microwave heating technology. It was demonstrated that the selected plastics meet the basic criterion that is transparency for electromagnetic radiation.Keywords: microwaves, permittivity, loss tangent, loss factor, foundry tooling W pracy podjęto wstępne badania nad ustaleniem kryteriów oceny przydatności materiałów do budowy oprzyrządowania odlewniczego, przewidzianego do zastosowania w technologii nagrzewania mikrofalowego. Przedstawiono wyniki pomiarów przenikalności elektrycznej oraz tangensa kąta stratności, które określają zachowanie materiałów w polu elektromagnetycznym. Pomiary przeprowadzono na stanowisku falowodowej wnęki rezonansowej, która umożliwia precyzyjne wyznaczenie metodą perturbacyjną wymienionych parametrów. Badaniom poddano pięć różnych materiałów przewidzianych do zastosowania w budowie oprzyrządowania odlewniczego. Określono współczynnik stratności, który pozwala, na ocenę przydatności materiałów w technologii nagrzewania mikrofalowego. Wykazano, że wybrane tworzywa sztuczne spełniają podstawowe kryterium, jakim jest transparentność dla promieniowania elektromagnetycznego.

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