BAKE Furnace Stability Explorer

Stability window by furnace atmosphere

Temperature range in which the compound is the thermodynamically stable phase at its own metal ratio. A solid bar is a stable window. A light dotted bar means the compound is above the hull but its equilibrium phases exchange no oxygen there. A diamond means it only touches the hull where two neighbouring phases coexist. A cross means it is not stable anywhere between 27 and 3000 °C. For a metal or intermetallic the window is where it stays unoxidised, so it usually opens at high temperature or in H₂.

Oxygen uptake

Equilibrium phase assemblage at the compound's metal ratio as the oxygen chemical potential changes. The y axis counts O atoms gained (+) or released (−) per formula unit. The green step is the compound itself (amber when it is above the hull). High-entropy compounds include configurational entropy, so this plot also changes with temperature. The top axis converts Δμ_O to oxygen partial pressure at the temperature set below, and the vertical lines mark the three atmospheres at that temperature.

Temperature 1000 °C

Ellingham diagram

Standard Gibbs energy per mole of O₂ of the reactions that involve this compound: its oxidation (solid) and its reduction (dashed), which it undergoes below the dashed line. The compound is stable in the green band between them; in the yellow band it is not oxidised but sits above the hull and may phase-separate. An atmosphere oxidises it wherever its curve lies above the solid line. Hover over a line for its reaction. The right-hand scale and dotted lines give p_O2.

Pure-metal oxidation lines Further oxidation and reduction steps

Phase sequence along μ_O

Method and data provenance