Attributed to their remarkable physical, chemical, thermal and mechanical properties, metallic glasses have been studied since their discovery in 1960s. Metallic glasses have unique amorphous structure with short-to-medium range order. They have many potential application areas due to their unique properties based on the combination of their amorphous and metallic character. This study presents the investigation of structure, thermal, mechanical properties and fracture behavior of Zr47.5Cu38Al9.5Sm5, Zr50Cu37Al10Sm3, and Zr50Cu35Al10Sm5 metallic glassy alloys using X-ray diffraction (XRD), scanning electron microscope (SEM), differential calorimetry (DSC), and mechanical testing under both as-cast and isothermally annealed conditions. Thermal analysis indicates the dependence of crystallization kinetics and mechanisms on the composition of the metallic glasses. The crystallization mechanism is mainly governed by interface-controlled three-dimensional growth with different nucleation rates. The hardness and fracture strength values were found to increase slightly with the increase of Sm content. The compression test results revealed different fracture mechanisms for the alloys. The fractured surface of Zr50Cu35Al10Sm5 rods consists of vein-like and river-like patterns regarding a combination of brittle and ductile fracture. The fracture mechanisms of Zr50Cu37Al10Sm3 and Zr47.5Cu38Al9.5Sm5 alloys revealed brittle fracture with cleavage mode. Zr47.5Cu38Al9.5Sm5 metallic glass shows the highest fracture strength. This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK) under contract number 117M295. ORCID NO: 0000-0001-8025-7751
Anahtar Kelimeler: Metallic glass, mechanical properties, thermal properties
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