Characteristics of microstructure evolution of two-phase H62 brass alloy during continuous extrusion

摘要

The initial grains of H62 brass alloy are refined after continuous extrusion, and the dynamic recrystallization occurs in the forming process. Mastering the driving forces of microstructure evolution are the key for exploring the deformation characteristics of two-phase H62 brass during continuous extrusion. The optical microscope (OM) and the transmission electron microscope (TEM) were used to observe the whole regions of H62 brass. The results show that the microstructure in groove rolling region is flatter than that in raw material. The dislocations and twins are found in α phases, and β phases are broken and distributed in the boundary of a phases in the adhesion region. The dynamic recrystallization is found in the right angle deformation region, and more dislocations and twins in α phases and more fine grains of β phases are found in this region than ones in the adhesion region. For extrusion deformation region, more dislocations in α phases and β phases, and more twins in α phases in lower part than ones in the upper part for this region, which indicates the key microstructure evolution concentrates on the lower part for extrusion deformation region. The results are benefit to guide obtaining the product with excellent properties.