摘要
采用光学显微镜(OM)、带能谱分析(EDAX)的扫描电子显微镜(SEM)、X射线衍射仪(XRD)等方法对Mg-11Y-5Gd-2Zn-0.5Zr(WGZ115)合金的原始铸态(F态)、固溶处理态(T4态)和峰值时效态(T6态)的组织结构进行了分析。研究表明:F态WGZ115合金主要由基体(-αMg)、晶间共晶相(Mg24(YGdZn)5)和长周期结构相(Mg12Y1Zn1)组成。T4态WGZ115合金主要由基体相(-αMg)、长周期结构相(Mg12Y1Zn1)和少量分布于晶界附近的方块相(Mg-Y-Gd方块相)组成。T6态WGZ115合金的形貌与T4态相似,圆形的富Zr相始终存在于三种状态的合金中。通过不同温度下的拉伸实验发现T4态WGZ115合金的抗拉强度和塑性好于F态合金。而T6态合金的力学性能最好,在200℃时抗拉强度达到最大值341.1MPa。
Microstructures of as-cast（F）,solution treatmented（cast-T4） and aging treatmented（cast-T6） Mg-11Y-5Gd-2Zn-0.5Zr（WGZ115） alloy were investigated using optical microscopy（OM）,scanning electron microscopy（SEM） with energy dispersive X-ray analyses（EDAX） and X-ray diffractometry（XRD）.The results show that the as-cast alloy is consisted of α-Mg,eutectic phase（Mg（24）（YGdZn）5） and needle-and plate-shaped long-period structure（Mg（12）Y1Zn1）.After solution treatment the WGZ115 alloy is consisted of α-Mg,LPSO phase and cube-shaped phases （cuboid Mg-Y-Gd） around the grain boundary. The microstructure of WGZll5 alloy after aging treatment is similar to that of solution treatment. Some Zr-rieh cores exist in the as-cast, east-T4 and cast-T6 samples. At different temperatures, the tensile properties of the as-cast WGZ115 alloy are the worst. The cast-T4 alloy has better strength and plastic performance than those of as-cast alloy. The cast-T6 alloy exhibits the best tensile properties with the maximum ultimate tension strength of 341.1MPa at 200℃.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2009年第6期829-833,共5页
Journal of Materials Science and Engineering
基金
国家973项目专题资助项目(6133001E)
