| Title |
Two - Stage Enthalpy Relaxation phenomenon for Metal - Metal type Fe - Co - Zr ( Hf ) Amorphous Alloys |
| Authors |
노태환(Tae Hwan Noh); 강일구(Il Koo Kang) |
| Abstract |
The enthalpy relaxation phenomenon for metal-metal type Fe-Co-Zr(Hf) amorphous alloys has been studied calorimetrically. The magnitude of the exothermic reaction resulted from the irreversible enthalpy relaxation in amorphous (Fe_(1-x)Co_x)_(90) Zr_(10) (x=0-1) alloys was the largest at x=0.5 The changes in ΔC_p(exo) with temperature for amorphous (Fe_(0.5)Co_(0.5))_(90)Zr_(10) and (Fe_(0.5)Co_(0.5))_(90) Hf_(10) alloys showed two stages, a low-temperature one which shows a peak at about 525K and a high-temperature one which shows a peak near Tx. The low-temperature reaction was ascribed to the rearrangement between Fe and Co atoms with weak bonding nature and the high-temperature one to the rearrangement between Fe, Co and Zr, Hf atoms with strong bonding nature. And it was noticed that the high-temperature relaxation causes the decrease in Curie temperature for amorphous Fe-Co-Zr alloys. |