热挤压工艺对Mg-Zn-Y-Zr合金组织性能的影响（英文）

Influence of Hot Extrusion Process on Microstructure and Mechanical Properties of Mg-Zn-Y-Zr Magnesium Alloy

对合金进行不同挤压参数的挤压试验,通过对实验结果的分析,来探究挤压工艺参数对镁合金的组织性能的影响规律。研究表明,合金在热挤压过程发生了明显的动态再结晶,与铸态组织相比晶粒得到了细化,力学性能也有了明显提升。合金中的第二相是W相,第二相在不同热挤压条件下,形态和分布差别较大。合金的组织和力学性能在挤压过程中受挤压温度和挤压比影响,随着挤压温度提高,合金的再结晶晶粒数量增加,但有长大的趋势,挤压温度为300℃时,合金强度最高;挤压比对合金塑性影响较大,挤压比为25时,合金的塑性显著提升。

The extrusion experiments at different extrusion parameters were performed; the effects of different extrusion parameters on the microstructure and mechanical property of Mg-4.8Zn-1.2Y-0.4Zr magnesium alloy were described, based on the experimental results and analysis. The result shows that dynamic recrystallization is observed after the hot extrusion process, the alloy grain is refined compared with as-cast alloy. The phase of the extruded alloy is W-phase; there are great differences in morphology and distribution between alloys with different extrusion parameters. The microstructure and mechanical properties of magnesium alloy are affected by extrusion temperature and extrusion ratio in the hot extrusion process. When the extrusion ratio is the same, the number of recrystallization grains increases with the increasing of temperature; meanwhile recrystallization grains also have a tendency to grow up. When the extrusion temperature is 300 ℃, the comprehensive mechanics performance of the alloy is the most excellent. The influence of extrusion ratio on the plasticity of the alloy is obvious; when the extrusion ratio is 25, the elongation of the alloy increases significantly.