KanjiJLPT N2
Melt

melt, dissolve, thaw

Mnemonic

A raging storm of pure heat blasts through your town. You try to contain it inside a steel vault, but the temperature is so extreme the vault itself begins to melt—walls dripping into liquid pools, nothing solid left.
Additional thoughts
Visualize a swirling vortex of white-hot fire (storm) locked in a steel box (contain). The box can't hold it and liquefies. Storm + Contain = Melt.
Quick recall
A storm of heat you try to contain causes everything to melt.

Details

The keyword for 溶 is melt. This kanji refers to the process of a solid substance dissolving or liquefying, typically through the application of heat or by being absorbed into a liquid. It covers both the sense of melting, as when ice turns to water, and dissolving, as when a substance breaks down and disperses within a solution. The character conveys the idea of something losing its solid form and merging fluidly into another medium.
On'yomi
よう
Kun'yomi
と.ける、と.かす、と.く