THE CRYSTALLIZATION PROCESS OF METGLASS (Fe 0.1 Co 0.55 Ni 0.35 ) 78 Si 8 B 14 AND THE EFFECT OF HIGH PRESSURE (II)——The Crystallization Temperature and The Crystallization Activation Energy

In this paper, the pressure dependence of the crystallization temperature T x and the crystallization activation energy △EX of metglass (Fe 0.1 Co 0.55 Ni 0.35 ) 78 Si 8 B 14 werestudied by measuring the electrical resistivity in-situ under pressure up to 3 GPas. It was found that application of high pressure not linearly, even not monotonicaly riases the T x , as usually described in literatures for pressure dependence of T x in metglasses, but shows some local detours on T x vs. P curve in a general rising tendency. △E x shows same behaviour analogous to that of T x as the pressure rises. An analytical discussion indicates that pressure promotes the nucleation process and restrains the diffusional growing up of the crystallized nuclei on heating the metglass. As a combined result of the mutual contrary effects of pressure on nucleation activation energy a,nd diffusion activation energy, it gives rise the above non-monotonic rising behaviour of △E x and T x of the metglass studied. In addition to △E x , pressure may also markedly affect the preexponential factor and produces a considerable change on crystallization temperature.