If we look at the Ellingham diagram, it becomes evident that the plots for Al and Mg cross each other at 1350^∘C1350^∘C (1623 K). Below this temperature, Mg can reduce Al₂O₃Al₂O₃ and above this temperature, Al can reduce MgO.

The temperature of the substance in liquid state is higher. The Ellingham diagram suggests that the value of ΔG for the formation of metal oxides increases as the temperature increases. The reduction of metal oxide to metal is possible if the Gibbs energy is negative. Therefore, the reduction of metal oxide to metal is easier if the metal obtained in liquid state.

Flux in the smelting process is added to, decrease the solubility of impurities, increase the fusion temperature of roasted ore and convert impurities into slag.
Flux removes the gangue to form easily fusible slag.
\(\mathrm{SiO}_{2}+\ \ \ \mathrm{FeO} \rightarrow\ \ \ \mathrm{FeSiO}_{3}\)
Acidicflux   Basicangue    Slag

18-8 Stainless Steel:
It is produced using approximate quantities of 18% chromium and 8% nickel, and it covers a family of fittings that include 302, 304, 305 and 384 stainless screws.
Screws made from 18-8 stainless steel are non-magnetic and have excellent resistance to rust and corrosion.

To satisfy low sulfur requirements for iron processed into steel, magnesium reagents in powder or granular form are used to remove sulfur via slag-liquid metal reactions done under reducing conditions, where sulfur is transferred out of the steel through the slag-metal interface, and into the slag.