Effect of Ta on solidification characteristics and mechanical properties of DZ411 Ni-based superalloy

作     者：Peng Peng Zi-jie Liu Yuan-li Xu Xu-dong Zhang Zhi-kun Ma Jia-tai Wang Peng Peng;Zi-jie Liu;Yuan-li Xu;Xu-dong Zhang;Zhi-kun Ma;Jia-tai Wang

作者机构：School of Materials and EnergyLanzhou UniversityLanzhou 730000China School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'an 710072China School of Physics and Electronic InformationQinghai Normal UniversityXining 810008QinghaiChina 

出 版 物：《中国铸造:英文版》 (China Foundry)

年 卷 期：2023年第20卷第5期

页      面：376-386页

核心收录：

学科分类：08[工学] 0806[工学-冶金工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：This study was funded by the National Natural Science Foundation of China(Grant No.51871118) the fund of the State Key Laboratory of Solidification Processing in NPU,(Grant No.SKLSP202204) the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2022-ey15). 

主　　题：DZ411 superalloy directional solidification Ta dendrite arm spacing microhardness 

摘      要：The effects of Ta content(2.72wt.%,3.10wt.%and 4.00wt.%)on the solidification characteristics and mechanical properties of directionally solidified DZ411 Ni-based superalloys were investigated.It is found that the content of Mo decreases with the increase of Ta in liquid phase after directional solidification,indicating the addition of Ta can reduce the element segregation in alloys.The primary and secondary dendrite arm spacings(PDAS and SDAS)of the DZ411 alloy increase with the addition of Ta,which are consistent with the models by Hunt and Wagner.The increase of PDAS and SDAS can provide enough space for the growth of tertiary dendrite arms,which hinders the growth of unfavorably oriented primary dendrites.As a result,the addition of Ta facilitates the growth of favorably oriented dendrites.More MC carbides andγ-γ eutectics are formed in the interdendritic regions,which is attributed to the segregation of Ta in the liquid phase.Furthermore,the degree of supersaturation of W,Mo inγmatrix increases with the increase of Ta,thus,the addition of Ta promotes the formation of TCP phase.The addition of Ta also increases the microhardness in both the primary dendrite and interdendritic regions of the alloy,and the microhardness of the primary dendrite is closer to that in interdendritic regions with the increase of Ta.