A-μ-PD法による難加工性合金の線材結晶化技術

抄録

  We developed a novel fabrication method for alloy crystal fibers with poor-workability by unidirectional solidification using an alloy-micro-pulling-down (A-μ-PD) method and ceramic crucibles with sufficient mechanical and thermal shock resistance. Ir, Pt, Ru and their alloy fibers were fabricated from the melt directly by the A-μ-PD method. Long alloy fibers could be obtained using a pinch-roller and winding machine. Ir and Ru fibers were composed of number of elongated grains oriented along a growth direction which is attributable to the unidirectional solidification. In addition, microstructure and mechanical properties of Co-Cr-Mo (CCM) alloy fibers fabricated by the A-μ-PD method could be controlled by the growth rate. Ratio of the fcc-γ-phase in the CCM alloy fibers systematically increased with increasing growth rate. The hcp-ε-phase CCM crystal fibers exhibited considerably improved strain because of the slipping line in the hcp structure.