論文
マグネシウム合金AZ31の多軸鍛造による
大ひずみ加工とその後の機械的特性
大ひずみ加工とその後の機械的特性
2007 年 48 巻 556 号 p. 407-411
詳細
2007 年 48 巻 556 号 p. 407-411
Grain refinement of magnesium alloy AZ31 was studied in multidirectional forging (MDF) under decreasing temperature conditions. MDF was carried out up to large cumulative strains of 5.6 with changing the loading direction during the decrease of temperature from pass to pass. MDF can accelerate the uniform development of very fine grain structures and increase the plastic workability at low temperatures. New grain structures with the minimal grain size of 0.23μm can be developed by continuous dynamic recrystallization at a final processing temperature of 403K. The MDF alloy showed higher strength, as well as high ductility, at room temperature and also superplastic elongation at 423K. The relationship between the yield stress or hardness at room temperature and the grain size can be represented by a Hall-Petch equation in strain-induced fine-grained magnesium alloy.
