Effect of adaptive nanocrystalline behaviors on the cavitation erosion performance of Cu_(47.5)Zr_(45.1)Al_(7.4)bulk metallic glass  

作　　者：Tongchao Xu Guoliang Hou Haobo Cao Junkai Ma Yulong An Huidi Zhou Jianmin Chen 

机构地区：[1]State Key Laboratory of Solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou 730000,China [2]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Journal of Materials Science & Technology》2024年第29期248-261,共14页材料科学技术(英文版)

基　　金：financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0470102);the Central Government Guides Local Science and Technology Development Fund Projects(Grant No.23ZYQA0320);the National Natural Science Foundation of China(Grant No.52175200);the Youth Innovation Promotion Association of the Chi-nese Academy of Sciences(Grant No.2020416);the Longyuan Youth Talent Project.

摘　　要：Amorphous alloys have attracted much attention in the field of cavitation erosion(CE)due to their good comprehensive properties.However,due to the special amorphous structures that are difficult to characterize,their micro-response behaviors and damage mechanisms during the CE process have not been well elucidated.In this paper,advanced techniques including focused ion beam(FIB)and transmission electron microscope(TEM)were used to comparatively study the microstructure evolution and volume loss rules of Cu_(47.5) Zr_(45.1) Al_(7.4) and Zr_(41.2) Ti_(13.8) Cu_(12.5) Ni_(10) Be_(22.5) bulk metallic glasses(BMG)under the action of cavitation load and cavitation heat to reveal their CE mechanisms.The results showed that the absence of small atoms in Cu_(47.5) Zr_(45.1) Al_(7.4) led to a large free volume,thereby compromising its hardness,modulus,and yield strength.However,this also made it more susceptible to shear banding,which in turn enhanced its energy absorption capabilities.Although Cu_(47.5) Zr_(45.1) Al_(7.4) had a higher glass transition temperature(T_(g))and onset temperature of crystallization(T_(x)),as well as a wider supercooled liquid phase region(△T_(x)),its exothermic peak was obviously pronounced and the transformation temperature range was significantly narrower.Therefore,it is more likely to adaptively form Cu-rich nanocrystals under the action of cavitation heat.Additionally,the larger free volume in the shear band was conducive to the diffusion of atoms and the occurrence of adaptive nanocrystallization behaviors in Cu_(47.5) Zr_(45.1) Al_(7.4).These nanocrystals were able to effectively force crack deflection,thereby dissipating impact energy and delaying the fatigue spallation of the material.Consequently,Cu_(47.5) Zr_(45.1) Al_(7.4) exhibited a far longer incubation period and a noticeably lower cumulative volume loss.

关 键 词：Amorphous alloy Cavitation erosion Cavitation heat NANOCRYSTALLIZATION Shear band 

分 类 号：TG1[金属学及工艺—金属学]