고강도 Fe基 비정질계 합금의 고온 변형 특성

Abstract

The high temperature mechanical behavior of a Fe-base amorphous and amorphous matrix composite were fabricated. The mechanical properties with varying temperature and strain rate were determined with compression test. Mixture of non-crystaline and crystaline phases were found usting X-ray diffraction (XRD) and differential thermal analysis (DTA) tests. Exothermic reaction obtained at 620℃ during heating with solid state transformation from metstable crystalline phase to stable phase. Based on crystallization temperature, compression tests were performed in the temperature ranging from 560℃ to 700℃ with 20℃ interval. The Fe based amorphous matrix composite exhibied considerable peak stress drop above 640℃ and strainrate of 5x10-3/s. To find the temperature and strain rate dependence on deformation behavior below crystallization temperature (Tx), compression tests with wide temperature ranges is under investigation, and relationship between microstructure, including fracture surface morphology, and mechanical behavior is being studied.