Abstract: A structure includes a substrate of a first material and a second material coating at least a portion of the substrate, where the second material is different from the first material, where the first and second materials, upon being thermally energized, react with each other in an exothermic and self-sustaining alloying reaction that propagates from a first location within the structure along a travel path to a second location within the structure at a rate that depends upon one or more characteristics of the first and second materials.

Abstract: A heat generating structure includes a substrate of a first material and a second material coating at least a portion and preferably all of the first material, where the second material is different from the first material. The structure also includes an additional material or compound such as ammonia borane that is impregnated or located within the structure. When the structure is thermally energized, the first and second materials react with each other in an exothermic and self-sustaining reaction that pyrolyzes the impregnated ammonia borane compound to create a target gas, for example, hydrogen from the ammonia borane. An additional material, for example, a thermite, may be interposed between the structure and the ammonia borane to facilitate the ignition of the ammonia borane.

Abstract: A structure includes a substrate of a first material and a second material coating at least a portion of the substrate, where the second material is different from the first material, where the first and second materials, upon being thermally energized, react with each other in an exothermic and self-sustaining alloying reaction that propagates from a first location within the structure along a travel path to a second location within the structure at a rate that depends upon one or more characteristics of the first and second materials.