Effect of CaF2 Additions on the Yield of AZ63 Magnesium Chips during Remelting

Year 2024, , 16 - 20, 15.01.2024

Pınar Yörük Mertol Gökelma

https://doi.org/10.34248/bsengineering.1356822

Abstract

Magnesium is one of the metals listed in European Union’s critical raw materials list. Primary production of magnesium is a high energy demanding process which raised the necessity of recycling the magnesium alloys in an efficient way. Remelting those scraps under a salt flux consist of chlorides (NaCl, KCl, and MgCl2) and fluorides (CaF2) are a common process however, different alloys might behave differently when it comes to salt-metal-metal oxide interactions. Furthermore, the condition of the salt flux such as dry-mixed or pre-melted (fused) affects the coagulation and metal yield. This work presents results on the effect of CaF2 concentration and pre-melting the salt flux on metal yield during remelting of chips. A yield up to 75% was observed in the case of remelting of chips under a fused salt flux with 5.5% CaF2 concentration.

Keywords

Recycling, Machining waste, Salt flux, Fluoride

Project Number

118C311

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