| 引用本文: | 张全福,宋蕾,王建,郭振宇,任乃栋,赵建琪,武维康,程伟丽.挤压态Mg-2Sn-2Bi-0.5Ca-0.2Mn合金的显微组织和力学性能[J].材料科学与工艺,2023,31(2):76-82.DOI:10.11951/j.issn.1005-0299.20220089. |
| ZHANG Quanfu,SONG Lei,WANG Jian,GUO Zhenyu,REN Naidong,ZHAO Jianqi,WU Weikang,CHENG Weili.Microstructure and mechanical properties of as-extruded Mg-2Sn-2Bi-0.5Ca-0.2Mn magnesium alloy[J].Materials Science and Technology,2023,31(2):76-82.DOI:10.11951/j.issn.1005-0299.20220089. |
|
| |
|
|
| 本文已被：浏览 257次 下载 289次 |
码上扫一扫！ |
|
|
| 挤压态Mg-2Sn-2Bi-0.5Ca-0.2Mn合金的显微组织和力学性能 |
|
张全福1 ,宋蕾1 ,王建1 ,郭振宇2,任乃栋1,赵建琪1 ,武维康1 ,程伟丽2
|
|
(1.孝义市东义镁业有限公司,山西 孝义 032308; 2.太原理工大学 材料科学与工程学院,太原 030024)
|
|
| 摘要: |
| 低合金化的Mg-Sn-Bi基合金具有较高的拉伸延展性和挤压成形性,是开发高强韧镁合金的理想材料。为了弥补其强度不足的缺点,本文通过微合金化设计了一种新型的低合金化Mg-2Sn-2Bi-0.5Ca-0.2Mn镁合金,该合金在挤压温度为523 K、挤压比为25∶1的条件下被成功挤压成形。采用电子背散射衍射仪(EBSD)、X射线衍射分析仪(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等技术表征挤压态合金的组织特征和相组成,并利用拉伸试验机测试了挤压态合金的室温拉伸性能,此外,还对合金的强韧化机制和加工硬化行为进行了详细的讨论。结果表明:挤压态合金主要由α-Mg、Mg3Bi2以及Mg2Bi2Ca相组成,且表现出几乎完全的动态再结晶组织和典型的挤压镁合金织构；合金的拉伸屈服强度为287.2 MPa,抗拉强度为353.0 MPa,伸长率为20.0%,具有良好的强韧性匹配度。合金展现出的高屈服强度是晶界强化、第二相强化和织构强化共同作用的结果；合金的断口形貌表现出典型的韧性断裂特征,然而粗大Mg2Bi2Ca相的存在会对塑性产生不利影响；合金的加工硬化行为可分为第Ⅰ阶段和第Ⅲ阶段,第Ⅱ阶段受到抑制。 |
| 关键词: Mg-Sn-Bi基合金 显微组织 力学性能 强化机制 加工硬化行为 |
| DOI：10.11951/j.issn.1005-0299.20220089 |
| 分类号:TG146.2 |
| 文献标识码:A |
| 基金项目:山西省留学回国人员资助项目 (2019032)；山西省镁合金重大科技专项项目 (20191102008). |
|
| Microstructure and mechanical properties of as-extruded Mg-2Sn-2Bi-0.5Ca-0.2Mn magnesium alloy |
|
ZHANG Quanfu1, SONG Lei1, WANG Jian1, GUO Zhenyu2, REN Naidong1, ZHAO Jianqi1, WU Weikang1, CHENG Weili2
|
|
(1. Xiaoyi Dongyi Magnesium Industry Co., Ltd., Xiaoyi 032308, China; 2. College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China)
|
| Abstract: |
| The low-alloyed Mg-Sn-Bi-based alloys have high tensile ductility and extrusion formability, which are ideal materials for developing magnesium alloys with high strength and ductility. Considering the poor strength of the alloy, a new low-alloyed Mg-2Sn-2Bi-0.5Ca-0.2Mn magnesium alloy was designed by micro-alloying, which was successfully extruded at an extrusion temperature of 523 K and an extrusion ratio of 25∶1. The microstructure and phase composition of the as-extruded alloy were analyzed by electron backscatter diffractometer (EBSD), X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM), and the tensile properties were tested by tensile testing machine at room temperature. In addition, the work-hardening behavior and strengthening and toughening mechanism of the alloy were discussed in detail. Results show that the as-extruded alloy was mainly composed of α-Mg, Mg3Bi2, and Mg2Bi2Ca phases, and exhibited almost complete dynamic recrystallization structure and typical extruded magnesium alloy texture. The studied alloy had a high strength-ductility with tensile yield strength (TYS) of 287.2 MPa, ultimate tensile strength (UTS) of 353.0 MPa, and elongation (EL) of 20.0%. The higher yield strength was the result of the combined effect of grain boundary strengthening, second phase strengthening, and texture strengthening. The fracture morphology of the alloy presented ductile fracture characteristics, while the presence of coarse Mg2Bi2Ca phases adversely affected the plasticity. The work-hardening behavior of the alloy could be divided into stage I and stage III, with stage II being suppressed. |
| Key words: Mg-Sn-Bi-based alloy microstructure mechanical properties strengthening mechanism work-hardening behavior |
|
|
|
|
