| Title |
Effect of Cooling Rate on the Mechanical Properties and the Microstructural Change of Zn-Al-Cu-Mg Alloys with Be |
| Authors |
오재청(Jae Cheong Oh) ; 박재용(Jae Yong Park) ; 강춘식(Choon Sik Kang) ; 김도경(Do Kyung Kim) ; 이경환(Kyeong Hwan Lee) |
| Abstract |
Zine alloys are widely used for materials of prototypical mold for small-quantity production and sample product since they have Low-melting temperature and good machinability for sample production of automobiles. In this study, Be was added as an alloying element to improve the tensile strength of Zn-Al-Cu-Mg alloys. The variations of tensile properties and microstructures according to Be additions were investigated. To investigate the effect of Be content on the tensile properties of these alloys depending on the cooling rates, 3-step terraced type metal mold and ceramic mold were used. As a result, Be type Cu-rich precipitates were formed by adding Be in Zn-Al-Cu-Mg alloys, and as the increase of Be contents, the precipitates were coarsened. The increase of the cooling rate made Zn-rich primary phase fine and the lamella arm space of eutectic phases decreased. In case of 0.006wt% Be content, tensile stregth was improved by about 10% and by increasing Be addition, tensile strength has been decreased. |