Microstructural evolution of BFe10-1-1 alloy tubes with continuous columnar grains during dieless drawing

作者：Yu Jun Wu; Liu Xue Feng^*; Xie Jian Xin

来源：Journal of University of Science and Technology Beijing, 2013, 35(1): 72-77.

• Alloy tube
• Columnar grain
• Continuous columnar grains
• Dieless drawing
• Drawing speed
• High thermal
• Pile-ups
• Process parameters
• Temperature range

The dieless drawing forming of BFe10-1-1 alloy tubes with continuous columnar grains was performed in a temperature range of 750-900°C at a drawing speed of 0.6-0.9 mm&middots-1. The microstructural evolution and mechanism of the tubes after the deformation was studied by optical microscopy, transmission electron microscopy, and X-ray diffraction analysis. It is found that the straight grain boundaries of columnar grains in the tubes become zigzag after dieless drawing within the process parameters of this paper. The sawtooth depth increases both with increasing drawing speed and temperature. Dislocations tend to pile up adjacent to grain boundaries and then travel over the grain boundaries, leading to gliding steps at the grain boundaries and consequently zigzag grain boundaries. Accompanied with the gliding deformation, thick continuous columnar grains start to rotate, increasing the zigzag degree. The high thermal activation energy and deformation-stored energy failed to release in time are the cause of maintaining continuous columnar grains in BFe10-1-1 alloy.

• 出版日期2013
• 单位北京科技大学