24/12/15 Yehuda Meir

Yehuda Meir

Ph.D. student of Prof. Eli Jerby

Electrical Engineering, Physical Electronics Department

Tel Aviv University

Localized Microwave Heating (LMH) and its Applications in Solids, Powders, and Plasmas

Abstract

Various LMH effects are presented in a paradigmatic approach. The LMH is intentionally induced, as in the microwave drill, by a near-field applicator to form a small hotspot. The thermal-runaway instability rapidly leads to a phase transition, to liquid, gas or plasma. Here we show that LMH can also be induced by low microwave power (~10 W) generated by a solid-state device such as LDMOS-FET. The LMH applicability is demonstrated for the ignition of thermite powders (mixtures of iron oxides and aluminum powders) with high ignition temperature (~1,500°C). Using the bubble-marble (BM) effect discovered in this study, thermite combustion also becomes feasible underwater. The hydrophobic powder is inserted as a confined BM into water, by an external magnetic field, and its combustion generates significant gas pressure underwater. Constructive LMH applications such as additive manufacturing of solid object from metal powders are presented. The inverse process of nano-powder production from solids is demonstrated as well by the LMH dusty plasma. The potentials and limitations of various LMH applications are discussed.

Thursday, December 24, 2015, at 15:00

Room 011, Kitot building