Abstract: A method of making an amorphous metal transformer core includes the steps of providing an amorphous metal core having two legs which are connected by an upper and a lower yoke, wrapping each of the legs with a sheet of flexible material which is capable of withstanding, without degradation, the temperature which is required to anneal the amorphous metal core, and then annealing the amorphous metal core. An amorphous metal transformer core includes a stack of amorphous metal laminations, the stack being formed into two legs which are connected by upper and lower yokes in which the legs are wrapped with a sheet of flexible material which is capable of withstanding, without degradation, the temperature required to anneal the amorphous metal core.

Abstract: Strips of cast amorphous metal material are folded to form segments of a transformer core. The segments are arranged in a stack or stacks that will ultimately become a transformer core. A single stack of folded segments is formed about a mandrel into the closed loop of a wound core. Two or more stacks of folded segments are arranged to form the closed loop of a stacked core. The stacks are annealed and the joints opened so that the stacks may be inserted into prewound windings. The joints are then reclosed to complete the transformer core-coil assembly.

Abstract: A transformer core is disclosed having one or more winding legs built up from a plurality of silicon steel laminations and a pair of yokes built up from a plurality of amorphous steel laminations. The yokes and legs are serially joined by silicon steel-amorphous steel lamination joints to create a magnetic loop circuit and thus provide a transformer core having significantly improved core loss characteristics as compared to a power transformer core formed exclusively of silicon steel laminations.