利用磁控溅射技术,在纯Ar和Ar-He混合气氛下制备CuAlTiWV高熵合金薄膜。利用场发射扫描电子显微镜(Field Emission Scanning Electron Microscope,FESEM)、高分辨透射电子显微镜(High Resolution Transmission Electron Microscope,HRT...利用磁控溅射技术,在纯Ar和Ar-He混合气氛下制备CuAlTiWV高熵合金薄膜。利用场发射扫描电子显微镜(Field Emission Scanning Electron Microscope,FESEM)、高分辨透射电子显微镜(High Resolution Transmission Electron Microscope,HRTEM)和X射线衍射仪(X-ray Diffraction,XRD)分别表征了薄膜的微观形貌和相结构,用划痕实验和FESEM研究薄膜的膜基结合强度和失效模型。结果表明:未掺氦且未退火CuAlTiWV高熵合金为非晶相基体上弥散分布着体心立方(Body Centered Cubic,BCC)相和金属间化合物相纳米尺寸粒子的结构。氦的引入和退火处理会影响薄膜的结晶度,但不会改变晶体结构类型。此外氦会使薄膜的表面产生鼓包,膜基界面处产生孔洞,从而使薄膜的临界载荷降低,失效模型由黏着失效转变为内聚失效。展开更多
It is widely accepted that helium(He) bubbles can prevent dislocations from moving and causing hardening and embrittlement of the material. However, He can affect the mechanical properties of materials in various ways...It is widely accepted that helium(He) bubbles can prevent dislocations from moving and causing hardening and embrittlement of the material. However, He can affect the mechanical properties of materials in various ways. In this work,ultrafine nanocrystal high entropy oxide(HEO) films with He implantation are prepared by using a radio frequency(RF)reactive magnetron sputtering system to investigate the effects of He bubbles located at grain boundary on the mechanical properties of the films. The mechanical properties of the HEO films are investigated systematically via nanoindentation measurements. The results indicate that the grain boundary cavities induced by He implantation can degrade the hardness,the elastic modulus, and the creep resistance of the HEO films. The mechanical properties of the HEO films are sensitive to the interaction between the He bubbles and the dominating defects.展开更多
Irradiation makes structural materials of nuclear reactors degraded and failed.However,the damage process of materials induced by irradiation is not fully elucidated,mostly because the charged particles only bombarded...Irradiation makes structural materials of nuclear reactors degraded and failed.However,the damage process of materials induced by irradiation is not fully elucidated,mostly because the charged particles only bombarded the surface of the materials(within a few microns).In this work,we investigated the effects of surface irradiation on the indirect irradiation region of the(Al0.3Cr0.2Fe0.2Ni0.3)3O4 high entropy oxide(HEO)films in detail by plasma surface interaction.The results show that the damage induced by surface irradiation significantly extends to the indirect irradiation region of HEO film where the helium bubbles,dislocations,phase transformation,and the nickel oxide segregation were observed.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11775150 and 11505121)
文摘It is widely accepted that helium(He) bubbles can prevent dislocations from moving and causing hardening and embrittlement of the material. However, He can affect the mechanical properties of materials in various ways. In this work,ultrafine nanocrystal high entropy oxide(HEO) films with He implantation are prepared by using a radio frequency(RF)reactive magnetron sputtering system to investigate the effects of He bubbles located at grain boundary on the mechanical properties of the films. The mechanical properties of the HEO films are investigated systematically via nanoindentation measurements. The results indicate that the grain boundary cavities induced by He implantation can degrade the hardness,the elastic modulus, and the creep resistance of the HEO films. The mechanical properties of the HEO films are sensitive to the interaction between the He bubbles and the dominating defects.
基金National Key Research and Development Program of China(Grant No.2017YFB0405702)the National Natural Science Foundation of China(Grant No.11775150).
文摘Irradiation makes structural materials of nuclear reactors degraded and failed.However,the damage process of materials induced by irradiation is not fully elucidated,mostly because the charged particles only bombarded the surface of the materials(within a few microns).In this work,we investigated the effects of surface irradiation on the indirect irradiation region of the(Al0.3Cr0.2Fe0.2Ni0.3)3O4 high entropy oxide(HEO)films in detail by plasma surface interaction.The results show that the damage induced by surface irradiation significantly extends to the indirect irradiation region of HEO film where the helium bubbles,dislocations,phase transformation,and the nickel oxide segregation were observed.
