Mg-Nd-Zn-Zr生物镁合金多向锻造组织演变及力学性能

Microstructure Evolution and Mechanical Properties of Mg-Nd-Zn-Zr Bio-magnesium Alloy of Multi-direction Forging Process

为了改善铸态Mg-Nd-Zn-Zr生物镁合金的力学性能,对其进行了多向锻造变形。利用光学显微镜、扫描电子显微镜、单向拉伸等手段研究了不同变形温度及不同道次对合金组织及力学性能的影响。结果表明,该合金多向锻的组织演变分为两个阶段,当温度较低且累积变形量较小时,其强韧化机制主要为变形过程中形成的合理锻造流线。试样经过450℃三道次变形后,其伸长率达到了0.271,抗拉强度达到了221 MPa,较铸态时的力学性能显著提高。

The multi-direction forging deformation was conducted to improve the mechanical properties of as-cast Mg-Nd-Zn-Zr bio-magnesium alloy. The effects of different deformation temperatures and different passes on alloy microstructure as well as mechanical properties were studied by optical microscope, SEM and uniaxial tension. The results show that the microstructure evolution of the alloy can be divided into two stages. When the temperature is lower and cumulative deformation is less, its strengthening and toughening mechanism is mainly about the formation of the reasonable forging streamline. After three passes deformation at 450℃, the elongation and tensile strength of the samples reache 0.271 and 221 MPa respectively, which are both improved significantly compared with those of the as-cast.