Reactive multi-layer foil

When the flame front reaches the edge of the material, particles of molten metal can be ejected, causing voids in the bond; this can be prevented by simultaneous ignition from more sides, so the flame fronts meet in the middle, confined by the substrates.

An externally applied even pressure during reaction and cooling serves to ensure a good homogeneous joint without voids.

[4] Significantly dissimilar materials can be bonded without cracking: semiconductors, metals, ceramics, and polymers.

[3] The energy is deposited very locally, without significant heating of the bulk of the substrates, which reduces problems with mismatched thermal expansion coefficients between the materials and allows their joining at room temperature.

The bonding process can be used in assembly of electronics, die attachment to heatsinks where high temperature stability is required (e.g. high-power LEDs or concentrated photovoltaics solar panels, soldering together layers of composite armor plates, bonding of large sputtering targets made of ceramics or refractory metals where normal indium based solders cannot be used, and other applications where a uniform joint over large area has to be created.

They can be employed in weapons as reactive materials, enhancing the energy delivery to the targets by the projectiles or their fragments.