%0 Journal Article
%T Effect of cooling rate on microstructure of B2-NiSc intermetallics
%A Chang
%A Yatao
%A Chen
%A Hao
%A Cui
%A Hongbao
%A Guo
%A Xuefeng
%A Yuan
%A Zhipeng
%J -
%D 2019
%R 10.30765/er.39.3.04
%X Sa£¿etak Ni-50at%Sc alloy was prepared by centrifugal casting method. Volume fraction, the actual content of B2-NiSc and second phase Ni2Sc in alloy were analyzed with an Image-Pro Plus software. The cooling rates for the solidified thin plate with thickness of 2.65mm, 1.2mm, 0.75mm and 0.35 mm are 1164, 2570, 4112 and 8811 K¡¤s- 1, respectively. It is found that d=0.5 mm was an critical dimension which corresponds to an abrupt change in the solidification rate. It is also found that (Ni2Sc+NiSc)eutectic was dispersed at grain boundary or between dendritic arms due to the loss of Sc element during melting. While d£¾ 0.5mm (corresponding to the thin plate with thickness of 0.75mm, 1.20mm and 2.65 mm), the solidification structure consists of primary phase B2-NiSc and (Ni2Sc+NiSc)eutectic. While d £¼ 0.5mm (corresponding to the thin plate with thickness of 0.35 mm), the solidification structure is composed of fine globular B2-NiSc and relatively small amounts of (Ni2Sc+NiSc)eutectic. Based on the phase volumetric analyzing of the microstructure with an Image-Pro Plus software, the loss of Sc element during melting was about 3.01~3.10 at%. The eutectic NiSc in the lamellar eutectic structure together with the primary phase B2-NiSc form a larger single phase NiSc, while Ni2Sc with the form of particles is distributed on the grain boundaries after (970 ¡æ, 72 h) homogenization heat treatment
%K centrifugal casting
%K B2-NiSc
%K microstructure evolution
%K rapid solidification
%K heat treatment
%K (Ni2Sc+NiSc)eutectic
%U https://hrcak.srce.hr/index.php?show=clanak&id_clanak_jezik=322839