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Prepared by FeCoNiCrAl Alloy and FeCoNiCrCu-alloy volume solidification microstructure equimolar ratio of the principal component alloy design ideas, using the vacuum electromagnetic induction melting method using directional solidification equipment, constant temperature gradient, prepared by changing the Withdrawal Rate up with different growth rate FeCoNiCrAl alloy and alloy FeCoNiCrCu the directional solidification structure. The use of optical microscopy, scanning electron microscopy, spectroscopy analyzer, X-ray diffraction (XRD), thermal analyzer principal component alloy microstructure, element distribution, phase composition, thermal properties and the study of the evolution of the directional solidification microstructure. By electrochemical experiments to study the multi-master alloy volume solidification microstructure and growth rate of 1μm / s directional solidification microstructure electrochemical corrosion behavior in 3.5% NaCl solution. XRD analysis showed that Alloy solidification process without the formation of a large number of brittle intermetallic compounds, there is only a simple phase structure, FeCoNiCrAl alloy bulk solidified as BCC structure FeCoNiCrCu alloy volume solidified organized as a single FCC structure solid solution. EDS analysis results showed that the enrichment in the interdendritic regions in FeCoNiCrAl alloy, Fe, Cr, Ni, Al enriched in the region of the dendrite, the Co content in the two regions considerable; the FeCoNiCrCu alloy, Fe, Co, Ni, Cr enriched in the region of the dendrite, Cu enrichment in the interdendritic regions. Increase with the growth rate in the range of experimental study,, FeCoNiCrAl alloy steady-state organization has undergone a plane crystal crystal cell crystal asperata crystal, twigs crystal evolution, crude cell; FeCoNiCrCu alloy steady state organization experienced a plane crystal cell crystal, cellular dendrites, dendrite evolution. With the solidification velocity increases, the two alloys are gradually refined grains FeCoNiCrAl alloy mainly through competitive growth, lateral branches develop into a spindle column spacing adjustment FeCoNiCrCu alloy is mainly eliminated through competition, cutting-edge cracking column spacing adjustment. In 3.5% NaCl solution, FeCoNiCrAl the alloy and FeCoNiCrCu alloy shows a similar electrochemical corrosion, i.e. solidified tissue by volume, the growth rate was 1μm / s directionally solidified microstructure in the order, the corrosion resistance increases, which is greatly reducing the number of directionally solidified alloy grain boundaries, the degree of segregation decreases, reducing the tendency to the formation of localized corrosion of the original battery.
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