Effects of minor Cu and Si additions on glass forming ability and mechanical properties of Co-Fe-Ta-B Bulk metallic glass

• Published in: Metals and materials international Vol. 22; no. 1; pp. 50 - 57
• Main Authors: Yazici, Ziya Ozgur, Hitit, Aytekin, Yalcin, Yilmaz, Ozgul, Metin
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Institute of Metals and Materials 01-01-2016; Springer Nature B.V; 대한금속·재료학회
• Subjects: Alloys; Amorphous alloys; Amorphous materials; Characterization and Evaluation of Materials; Chemistry and Materials Science; Cobalt; Composition effects; Compression tests; Compressive strength; Copper; Copper base alloys; Diamond pyramid hardness; Engineering Thermodynamics; Glass formation; Glassy; Hardness; Heat and Mass Transfer; High strength alloys; Iron; Machines; Magnetic Materials; Magnetism; Manufacturing; Materials Science; Mechanical properties; Metallic glasses; Metallic Materials; Microscopy; Optical microscopy; Processes; Silicon; Solid Mechanics; 재료공학; compression test; casting; microstructure; amorphous materials; thermal analysis
• ISSN: 1598-9623; 2005-4149
• DOI: 10.1007/s12540-016-5220-9

Effect of Cu and Si substitutions for Co and B on the glass forming ability (GFA) of Co
(43-x)
Cu
x
Fe
20
Ta
5.5
B
(31.5-x)
Si
y
(x=0-1.5 and y=5-10) were systematically investigated by X-ray diffraction, optical microscopy, scanning electron microscopy, and differential scanning calorimetry. In order to evaluate the contribution of copper and silicon, appropriate amounts of copper and silicon were individually introduced to the base alloy composition. By using the effects of copper and silicon together, significant enhancement was obtained and the critical casting thickness (CCT) of the base alloy was increased three times from 2 mm to 6 mm. Moreover, mechanical properties of the alloys were examined by compression tests and Vickers hardness measurements. The compression test results revealed that the glassy alloys having enhanced GFA shows high strength of about 3500-4000 MPa. In addition, existence of (Co,Fe)
2
B and (Co,Fe)
20.82
Ta
2.18
B
6
crystalline phases in glassy matrix influences the hardnesses of the alloys compared to monolitic glassy structure having hardness of about 1200 Hv.