| abstract |
A primary ultrafine-crystalline alloy having a composition represented by the general formula: Fe 100-x-y-z A x B y X z , wherein A is Cu and/or Au, X is at least one element selected from the group consisting of Si, S, C, P, Al, Ge, Ga and Be, and x, y and z are numbers (by atomic %) meeting the conditions of 0 < x ¤ 5, 10 ¤ y ¤ 22, 0 ¤ z ¤ 10, and x + y + z ¤ 25, and a structure in which 5-30% by volume of primary ultrafine crystal grains having an average particle size of 30 nm or less are dispersed in an amorphous matrix; its differential scanning calorimetry (DSC) curve having a first exothermic peak and a second exothermic peak lower than the first exothermic peak between a crystallization initiation temperature T X1 and a compound precipitation temperature T X3 ; and a ratio of the heat quantity of the second exothermic peak to the total heat quantity of the first and second exothermic peaks being 3% or less. |