Quenching from the solid state

1 Quenching (front the solid state). Metastable alloys have been very familiar to metallurgists for a long time now. Several alloys employed in everyday applications contain metastable phases. Typical examples are quenched steels and precipitation hardened aluminium alloys. Until the 1960s, metastable alloys were always obtained by quenching (rapid cooling) from the solid state. 

The traditional techniques for retaining a metastable phase in the solid alloy generally make use of the high-heat transfer from the hot solid to a fluid (a gas or a liquid). 

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