Abstract: Proposed is a compact high-temperature exothermic device by utilizing the heat of reaction of a reactive metal powder, e.g., titanium and zirconium, and a powder of boron and/or carbon mixed together in about the stoichiometric proportion forming a calorific mixture. The exothermic device is constructed by filling a hermetically sealable container of a metallic or ceramic material with the calorific mixture which is contacted at one end portion with an ignition means to cause ignition of the calorific mixture by supplying, for example, electric energy. The ignition means can be hermetically sealed in the container and the electric circuit of the ignition means comprises a switching means with a coil spring consolidated with a solder alloy in a constricted state in such a fashion that, when the solder alloy is melted down by heating from outside, the coil spring is released to close the electric circuit by bringing a contact point held thereon into contact with a couterpart contact point.

Abstract: A shaped body of a refractory or other functional inorganic compound of a metal, e.g., borides, carbides, silicides, etc. of titanium, zirconium, niobium and the like in a plate-like form can be prepared by an in situ reactive sintering method in which a metal-made flat reaction capsule is filled with a mixture of the reactant powders to form a powder compact which is ignited at a periphery while the capsule is under hydraulic compression so that the exothermic reaction is efficiently and almost instantaneously propagated within the plane of the plate-like powder compact. The liquid compression medium communicates to an accumulator filled with a compressed gas so that the otherwise unavoidable sudden pressure decrease due to the shrinkage of the powder compact can be compensated by the expansion of the compressed gas to keep constancy of the pressure.

Abstract: A method of producing a material having a layer of ceramic as a first component, a layer of a metal as a second component and an intermediate layer lying between said layers and including said first and second components in continuous gradient ratios so that the properties of the material may change continuous, including a step of forming said intermediate layer by igniting a powder mixture of metallic and nonmetallic constitutive elements of said ceramic component and said metal component so as to cause a synthetic reaction in the powder mixture.