| 학회 |
한국재료학회 |
| 학술대회 |
2016년 봄 (05/18 ~ 05/20, 여수 디오션리조트 ) |
| 권호 |
22권 1호 |
| 발표분야 |
D. 구조 재료 분과 |
| 제목 |
Crystallization kinetics and thermo-mechanical behavior on supercooled liquid region of Ti-Cu-Ni-Zr-Sn-Si bulk metallic glass |
| 초록 |
In this study, we investigate crystallization kinetics and thermo-mechanical behavior of Ti42.6Cu40.8Ni7.65Zr5.4Sn2.55Si1 bulk metallic glass (BMG) to evaluate the thermoplastic formability in the supercooled region. The crystallization kinetics was investigated by isochronal and isothermal annealing on supercooled liquid region (SLR). The activation energy for onset crystallization calculated from Kissinger equation is 334.4 ± 2.3 kJ/mol, which is higher than that of other reported Ti-based BMGs. The incubation time before crystallization measured from isothermal annealing with different temperaures is 13.83 min for 706 K, 9.51 min for 716 K, 2.22 min for 722 K, 1.76 min for 730 K and 0.71 min for 738 K, respectively. Viscosity measurement displays a strong viscosity drop in the range from 108 to 106 Pa∙s within SLR with increasing temperature. From the time-temperature-transformation (TTT) curve obtained from isothermal annealing and the viscosity measurement within supercooled liquid region, the optimal thermoplastic forming processing condition can be obtained as follows: temperature = 730 K, time = 60 s and pressure = 40 MPa. The laboratory-scale thermoplastic forming experiment exhibits successfully replicated imprinting feature on the surface of the thermoplastically formed sample without crystallization of amorphous phase. These results demonstrate that thermoplastic forming can be suitably facilitated by exploring the crystallization kinetics and viscous flow behavior within supercooled liquid region. |
| 저자 |
Sung Hwan Hong1, Jeong Tae Kim1, Hae Jin Park1, Young Seok Kim1, Young Sang Na2, Ka Ram Lim2, Jin Kyu Lee3, Ki Buem Kim1
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| 소속 |
1Sejong Univ., 2Korea Institute of Materials Science, 3Kongju National Univ. |
| 키워드 |
Bulk metallic glass; Crystallization kinetics; Activation energy; Viscosity; Thermoplastic forming
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| E-Mail |
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