Recalescence Velocity and Microstructure Evolution of Deeplyundercooled Cu65Ni35 Alloy

Abstract

The Cu65Ni35 alloy liquid was undercooled by the fluxing method, and the rapid solidification structure was obtained by natural cooling. The solidification interface migration information of Cu65Ni35 alloy liquid in rapid solidification stage was photographed with the help of high-speed camera, and the recalescence velocity was calculated. The microstructure evolution of the alloy was systematically studied by observing the microstructure morphology and taking photos on the metallographic microscope. By analyzing the evolution of dendrite grain size and microstructure microhardness with undercoolingand relying on electron backscatter diffraction (EBSD) technology, the grain refinement mechanism of microstructure under high undercooling and low undercooling is finally confirmed.

Keywords

rapid solidification / recalescence velocity / microstructure evolution

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