Finite element simulation of hybrid microwave sintering based on power approach

Akeem Damilola Akinwekomi, Ka Wai Yeung, Chak Yin Tang, Wing Cheung Law, Gary Chi Pong Tsui

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

Microwave (MW) sintering offers higher heating rate, rapid processing, reduced energy consumption, and reduced sintering temperature. However, the technique is not fully understood, difficult to control, and often relies on experience and trial-and-error approach. Consequently, hot spots, uneven heating, thermal runaway, and shape distortion develop in sintered compacts. Therefore, developing a model that can simulate the sintering process, enhance predictability, and determine the critical sintering conditions is essential. Multiphysics finite element (FE) modelling of hybrid MW sintering of a magnesium alloy AZ61 compact was undertaken in this study. The FE model coupled the electromagnetic, heat conduction, and densification equations. The model utilised parameters related to the furnace, compact, and susceptor to predict the spatial distribution of electric field, thermal response, and densification in the compact. A power-based sintering criterion was developed to predict the sintering of the compact and estimate its critical sintering energy. Modelling results showed that heating time, compact size, and thickness of the susceptor are critical to the sintering process. It was also shown that the susceptor not only mediated the sintering of the compact but also homogenised its temperature and densification. Thus, MW sintering of the compact was predicted to occur at 500 °C for 8 to 10 min with a predicted relative density of about 0.98. Experimental MW sintering data showed good concurrence with the developed model. These results are useful for controlling the MW sintering process, eliminating trial-and-error, and determining the critical sintering conditions.

Original languageEnglish
Pages (from-to)2503-2515
Number of pages13
JournalInternational Journal of Advanced Manufacturing Technology
Volume110
Issue number9-10
DOIs
Publication statusPublished - 1 Oct 2020

Keywords

  • AZ61
  • Densification
  • Finite element model
  • Hybrid sintering
  • Microwave sintering
  • Sintering criterion

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Software
  • Mechanical Engineering
  • Computer Science Applications
  • Industrial and Manufacturing Engineering

Cite this