Excellent high-temperature strength of(HfZrTiTaNb)C high-entropy carbide diffusion-bonded joint via in-situ alloying of Ni/Nb/Ni composite interlayer  

作　　者：Ruijie Mu Ying Wang Shiyu Niu Kongbo Sun Zhenwen Yang 

机构地区：[1]Tianjin Key Laboratory of Advanced Joining Technology,School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China [2]Key Laboratory of Advanced Ceramics and Machining Technology,Ministry of Education,Tianjin 300350,China

出　　处：《Journal of Advanced Ceramics》2025年第1期127-133,136-139,共11页先进陶瓷(英文)

基　　金：the financial support from the National Natural Science Foundation of China(Nos.52175357 and 52222511).

摘　　要：To obtain high-entropy carbide(HEC)joints with excellent high-temperature performance,a(HfZrTiTaNb)C HEC joint featuring a direct diffusion-bonded interface with a Nb-based interlayer was successfully fabricated at relatively low temperatures of 1150–1250℃for 60 min under 10 MPa.Starting from a modified Ni/Nb/Ni composite interlayer with a Nb content of>64 at%,an alloyed Nb_(2)Ni layer was constructed in situ by accelerating the directional diffusion of Ni atoms from the high-entropy interface into the remaining pure Nb through the Ni‒Nb eutectic liquid.Moreover,the excess liquid phase was squeezed out of the bonding region,ensuring the absence of Ni-based compounds.Leveraging the intrinsic interfacial stability and sluggish diffusion effect,the HEC with its original lattice structure,was capable of developing diffusion bonding with the Nb_(2)Ni layer instead of interacting with the liquid phase.The high reliability of the HEC/Nb_(2)Ni bonded interface was confirmed by the coherence of(11¯3)_(HEC)//(141)_(Nb_(2))Ni and a calculated lattice misfit of 0.044.The HEC joint had a high room-temperature strength of 174 MPa because of the homogenous Nb_(2)Ni layer,which exhibited nanohardness(15.2±1.5 GPa)and an elastic modulus of 219.9±17.5 GPa.Furthermore,the strength of the HEC joint did not decrease at 1000℃,increasing by~49%over that of HEC/Ni/HEC diffusion-bonded joints,which have stringent surface flatness requirements.This suggested that the HEC/Nb_(2)Ni interface had excellent resistance to high-temperature softening,even though it was invariably the initial failure location.This work is informative for designing bonding structures and preparing HEC components.

关 键 词：high-entropyceramic diffusion bonding in situ alloyed interlayer mechanical properties 

分 类 号：TQ174.1[化学工程—陶瓷工业]