논문 국내 국내전문학술지(KCI급) Oxidation Behaviors of Alloys Containing β/B2 Phases of Ti-45Al-Mo-Nb Alloys and Evaluation of the Oxidation Behaviors of Si Pack Cementation Coated Alloys
- 학술지 구분 국내전문학술지(KCI급)
- 게재년월 2019-03
- 저자명 Kwangsu Choi1, Youngbuem Song2, Seonghoon Yi3,*, and Joon Sik Park1,*
- 학술지명 대한금속·재료학회지
- 발행처명 대한금속·재료학회
- 발행국가 국내
- 논문언어 한국어
- 전체저자수 4
홈페이지
논문 초록 (Abstract)
Alloys containing the β/B2 phases of Ti-45Al-3Mo, Ti-45Al-3Mo-2Nb and Ti-45Al-5Mo were prepared using an vacuum arc-melting machine. Heat-treatments were carried out at 1250 °C in an Ar atmosphere. The temperature of 1250 °C is the temperature region of phase α + γ + (β/B2), and the heat treatment condition which improves mechanical properties by decreasing the fraction of the β/B2 phase. The presence of the β/B2 phase can result in relatively weakness at high temperatures and collapses the lamellar structure of the α2 / γ phase during heat treatment. The transient oxidation behaviors of Ti-45Al-(3, 5)Mo-(2Nb) (at%) alloys were investigated in an ambient atmosphere at 900 and 1000 °C. Initial oxidation behaviors and oxidation resistance of the three alloys were compared at 1000 °C. The oxidation resistance of the Ti-45Al- 3Mo-2Nb alloy containing Mo and Nb was the most remarkable among the three alloys at 900 °C and 1000 °C. At the same time, Si pack cementation coated Ti-45Al-3Mo-2Nb alloys and oxidation behavior were also analyzed. The phase sequences of the multilayers of τ2 / Ti5Si4 / TiAl3 / TiAl2 /TiAl were observed on the substrate. Also, a diffusion pathway of the silicide coating layers in the ternary phase diagram of Ti-Al-Si was proposed. The oxidation resistance of the silicide coated TiAl alloys was improved during the oxidation tests at 1000 °C.