Effect of solidification rate on dendrite segregation and mechanical properties of Cu-15Ni-8Sn alloy prepared by directional solidification  

作　　者：Yu-fan Shi Cheng-jun Guo Ming-quan Yuan Zhen-bin Jia Gui-huan An Xiang-peng Xiao Bin Yang 

机构地区：[1]Faculty of Materials Metallurgy and Chemistry,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China [2]Jiangxi Advanced Copper Industry Research Institute,Yingtan 335000,Jiangxi,China

出　　处：《Journal of Iron and Steel Research International》2023年第8期1586-1597,共12页

基　　金：supported by the National Key Research and Development Program of China(Grant No.2020YFA0714400);Science and Technology Projects of Jiangxi Provincial Department of Education(Grant Nos.GJ210843 and GJJ200873);Scientific Research Starting Foundation for Advanced Talents of Jiangxi University of Science and Technology(Grant No.205200100570);the Project of the Key Scientific and Technological of Jiangxi Province(Grant No.20181BCB19003);Ningbo Enterprise Innovation Consortium Special Project(Grant No.2021H003).

摘　　要：The microstructures and mechanical properties of the directionally solidified Cu-15Ni-8Sn alloy were investigated at solidification rates ranging from 100 to 3000μm/s.The results showed that the solidification rate significantly affects the phase distribution of the as-cast Cu-15Ni-8Sn alloy.The primary and secondary dendritic spacing reduces and eventually becomes stable as the solidification rate increases.Meanwhile,the size of the primary phase decreases,and its distribution becomes more uniform.The most severe segregation problem of this alloy has been greatly improved.Upon solidification at 100μm/s,the as-cast Cu-15Ni-8Sn alloy consists of the α-Cu matrix,γ-CuNi_(2)Sn phase,discontinuous precipitation structure,modulated structure,and DO_(22) ordered phases.However,as the solidification rate increases,the discontinuous precipitation structure,modulated structures,and DO_(22) ordered phases decrease and even disappear,reducing hardness.As the solidification rate increases,after homogenization treatment,the composition and microhardness distributions of Cu-15Ni-8Sn alloy become more uniform.The time for homogenization is also shortened.It reduces production energy usage and facilitates further mechanical processing.

关 键 词：Cu-15Ni-8Sn alloy Dendrite segregation Directional solidification Discontinuous precipitation structure DO_(22)ordered phase 

分 类 号：TB333[一般工业技术—材料科学与工程]