불연속 석출된 Al-Zn 합금의 상온 및 극저온 인발에 따른 미세조직
변화가 기계적 특성에 미치는 영향 |
김민수1,2, 한승전2,*, 이재현1,*, 임성환3, 안지혁2, 김상식4, 김광호5 |
1창원대학교 신금속재료공학과 2한국기계연구원 부설 재료연구소 소재실용화 연구실 3강원대학교 나노응용공학과 4경상대학교 금속재료공학과 5부산대학교 재료공학과 |
Mechanical Properties of Discontinuous Precipitated Al-Zn Alloys after Drawing at Room and Cryogenic Temperatures |
Min Soo Kim1,2, Seung Zeon Han2,*, Jehyun Lee1,*, Sung Hwan Lim3, Jee Hyuk Ahn2, Sang-Shik Kim4, Kwang Ho Kim5 |
1Department of Materials Science and Engineering, Changwon National University, Changwon 51140, Republic of Korea 2Commercialization Research Division, Korea Institute of Materials Science, Changwon 51508, Republic of Korea 3Department of Nano Applied Engineering, Kangwon National University, Chuncheon 24341, Republic of Korea 4Department of Materials Engineering and Convergence Technology, Gyeongsang National University, Jinju 52828, Republic of Korea 5School of Materials Science and Engineering, Pusan National University, Pusan 46241, Republic of Korea |
|
Received: 22 July 2016; Accepted: 16 August 2016. Published online: 2 February 2017. |
|
| |
ABSTRACT |
In order to study the effect of microstructural change on the tensile properties of discontinuous precipitated Al-Zn binary alloy, four different Al-Zn alloys(25, 30, 35, 45 wt% Zn) were aged at 160 ℃ for different aging times(0, 5, 15, 30, 60, 120, 360 min) after being solution treated at 400 ℃, and successively drawn at room and cryogenic temperatures(-197 ℃). Discontinuous precipitation was formed during aging in the Al matrix(which contained more than 30 wt% Zn) in Al alloys containing more than 30 wt% Zn. The tensile strength of continuous precipitated Al-35Zn alloy decreased with increasing drawing ratio, however, the tensile strength of discontinuous precipitated Al-35Zn alloy increased with further drawing. The strength and ductility combination, 350 MPa-36% was achieved by drawning discontinuous precipitated Al-Zn alloy at room temperature. The discontinuous precipitated Al-Zn alloy drawn at cryogenic temperature showed a higher value of tensile strength, over 500 MPa, although ductility decreased. |
Keywords:
Al-Zn alloys, continuous precipitation, mechanical property, microstructure, discontinuous
precipitation |
|