논문 국내 국제전문학술지(SCI급) Oxidation Behaviors of Alloys Containing beta/B2 Phases of Ti-45Al-Mo-Nb Alloys and Evaluation of the Oxidation Behaviors of Si Pack Cementation Coated Alloys
- 학술지 구분 국제전문학술지(SCI급)
- 게재년월 2019-03
- 저자명 박준식,최광수,송영범,이승훈
- 학술지명 KOREAN JOURNAL OF METALS AND MATERIALS
- 발행처명 KOREAN INST METALS MATERIALS
- 발행국가 국내
- 논문언어 한국어
- 전체저자수 4
홈페이지
논문 초록 (Abstract)
Alloys containing the beta/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 degrees C in an Ar atmosphere. The temperature of 1250 degrees C is the temperature region of phase alpha + gamma + (beta/B2), and the heat treatment condition which improves mechanical properties by decreasing the fraction of the beta/B2 phase. The presence of the beta/B2 phase can result in relatively weakness at high temperatures and collapses the lamellar structure of the a alpha(2)/gamma 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 degrees C. Initial oxidation behaviors and oxidation resistance of the three alloys were compared at 1000 degrees 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 degrees C and 1000 degrees 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 tau(2)/ 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 degrees C.