大尺寸ZK60镁合金挤压型材的组织与力学性能  

Microstructure and Mechanical Properties of Large ZK60 Magnesium Alloy Extruded Profiles

作　　者：李金柱[1,2] 郑开宏[1] 王顺成[1] 赵明纯[2] 

机构地区：[1]广东省工业技术研究院(广州有色金属研究院)金属成型与加工技术研究所,广东广州510650 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《热加工工艺》2014年第5期20-23,26,共5页Hot Working Technology

基　　金：广东省科技厅省部产学研结合项目(2010A090200078);广东省科技厅省部产学研结合科技创新平台建设项目(2012B090600051)

摘　　要：在挤压温度400℃、挤压速度5 mm/s、挤压比25的条件下成形了外接圆准179 mm的ZK60镁合金工字型材。运用XRD衍射、光学显微镜、扫描电镜及室温拉伸等检测手段对它的组织和力学性能进行了研究。结果表明,挤压态ZK60镁合金主要存在α-Mg、MgZn2相和少量Mg2Zn11、Zn2Zr3相。合金晶粒受挤压作用而破碎,发生不完全动态再结晶,晶粒得到明显细化,并沿挤压方向呈流线分布。细小的第二相颗粒弥散分布于α-Mg基体。室温拉伸实验说明挤压态ZK60镁合金存在明显的各向异性,挤压方向试样抗拉强度最高(325 MPa),与挤压方向成45°的试样伸长率最高(23%)。Abstraet：ZK60 magnesium alloy I-shaped sections profiles with circumcircle diameter 179mm were formed under the conditions of the extrusion temperature 400℃, the extrusion speed 5mm/s and the extrusion ratio 25. The microstructures and mechanical properties of the profiles were studied by using XRD, optical microscopy, scanning electron microscopy and tensile test method at room temperature. The results indicate that there are α-Mg, MgZn2 main phases and a small amount of Mg2Zn11, Zn2Zr3 phases. Alloy grains are broken by squeezing action, and the alloy produces incomplete dynamic recrystallization during the extrusion process, the graines are refined and distributed along the extrusion direction in a streamline. The fine second phase particles disperse in α-Mg matrix. Tensile test at room temperature shows that the extruded ZK60 magnesium alloy has obvious anisotropy. The tensile strength of the sample in extrusion direction is the highest （325MPa） and the elongation of the sample with the extrusion direction 45° is maximum （23%）. Key words ：ZK60 magnesium alloy; extruded profiles; mierostructure; anisotropy

关 键 词：ZK60镁合金 挤压型材 显微组织 各向异性 

分 类 号：TG379[金属学及工艺—金属压力加工]