Nonequilibrium alloys

Recently " we propo.sed to describe the nonequilibrium alloy kinetics using the fundamental master equation for probability P of finding the occupation number set... 

Traditionally, the electrochemical analysis of thin layers of electrodeposited nonequilibrium alloys has simply involved either galvanostatic or potentiostatic dissolution of the electrodeposit under conditions where passivation and/or replacement reactions can be avoided [194, 195]. A technique based on ALSY at a RDE has also become popular [196], To apply this technique, a thin layer (a 10 pm) of the alloy of interest is deposited on a suitable electrode in a solution containing the reducible ions of the alloy components. The plated electrode is then removed to a cell containing an electrolyte solution that is devoid of ions that can be reduced at the initial potential of the experiment, and the complete electrodeposit is anodically dissolved from the electrode surface using slow scan ALSV while the electrode is rotated. 

We also list three other alloy phase types of current interest that are not treated here in detail. Quasicrystals are alloy phases partially or completely lacking translational symmetry (see Quasicrystals) they form both equilibrium and nonequilibrium alloy phases. Metallic glasses lack crystalline symmetry entirely they are always metastable and generally require gas-phase deposition or rapid solidification to be retained, although in some cases their equilibration kinetics are so slow that they can be prepared in bulk from the melt (bulk metallic glasses). 

Recently " we proposed to describe the nonequilibrium alloy kinetics using the fundamental master equation for probability P of finding the occupation number set rii — a, for example, in a binary alloy A-B, where n,- = nf = 1 if the site i is occupied by an A atom, and n,- - 0 otherwise ... 

Miller P L, Shaw B A, Wendt R G and Moshier W C (1993), Improving corrosion resistance of magnesium by nonequilibrium alloying with yttrium , Corros. 49, 947-950. 

Miller PL, Shaw BA, Wendt RG, Moshier WC, Improving the corrosion resistance of magnesium by nonequilibrium alloying with Y , Corrosion, 1993 49 947-950. 

For a given alloy, the nonequilibrium solidus (average solid composition) can be calculated as a function of the temperature. The average composition of the solid,... 

Plot of the nonequilibrium solidus for an alloy of 1% B, superimposed on the phase diagram. 

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