Записки Горного института (Oct 2017)
Production of flat parts from foam aluminum in alternating magnetic field
Abstract
The electromagnetic technology for production of ultralight panels of materials based on foam aluminum is investigated. The theory of the interaction of the electromagnetic field with matter in the solid-liquid state and the formation of its corresponding distribution in space and time for the implementation of new technologies and equipment are considered. The suggested technology for the production of ultralight panels of materials based on foam aluminum include the following main stages: loading of powdered raw materials; preparation of the blank and the formation of the container; compacting (consolidation) by hot rolling; foaming of the preform precursor; production of a marketable product. The most difficult task is the process of heating the precursor to the temperature of foaming. In the course of the research, two possible modes of blank heating – static and periodic with reciprocating motion – were considered. The requirements for ensuring the temperature field of heated blanks for the production of foam aluminum are presented. The determining factor in the selection of the heating mode is the criterion for the quality of the blank heating. The main parameters that provide the required temperature field are the selection of the blank heating mode; speed of workpiece movement, and frequency selection. The displacement amplitude for reciprocating motion was chosen based on the available theoretical and practical experience of heating in this mode. The choice of frequency was influenced by several parameters, such as efficiency, voltage and current of the inductor, and its reactive power. The optimization of the process of electromagnetic processing of flat products on the basis of foam aluminum according to the results of numerical simulation makes it possible to develop an electromagnetic system for influencing metals in the solid-liquid state.