Effects of addition of Sn and Ni elements on the solidification structure of undercooled Ag-28.1Cu eutectic alloy
In order to reveal the influence and mechanism of Sn and Ni elements with different solid solubility in eutectic phase on the undercooled eutectic solidification structure,Ag-28.1Cu-xM(x=Owt.％,0.5wt.％,1wt.％;M=Sn,Ni)eutectic alloys were prepared using a combination of molten glass purification and cyclic superheating method.The effect of the third component Sn and Ni on the solidification structure of undercooled Ag-Cu eutectic alloy was investigated.The results showed that the addition of Sn did not change the macroscopic zoning characteristics of the microscructure.Moreover,an anomalous increase in eutectic and coarsening was observed in the microstructure,with a random orientation distribution.During solidification,Sn formed a concentration gradient perpendicular to the solid-liquid interface,resulting in the instability of the cellular interfaces and the formation of dendrites,but still maintaining coupled eutectic growth.While the addition of Ni eliminated the macroscopic zoning characteristics.In the microstructure,single-phase dendrites were formed,exa single orientation distribution.This is because Ni diffused parallel to the solid-liquid interface,causing the eutectic alloy growth to transit from coupled growth to decoupled growth.
Ag-28.1Cu eutectic alloydeep undercoolingalloying elements Sn and Nisolidification struc-tureEBSD
万方数据
维普
