Cr effects on the electrical contact properties of the Al 2 O 3 -Cu/15W composites

Nanotechnology Reviews

article

Xiaohui Zhang¹  Yi Zhang¹  Baohong Tian¹  Yanlin Jia²  Yong Liu¹  Kexing Song¹  Alex. A. Volinsky³  Huihui Xue¹ 

[1] School of Materials Science and Engineering, Henan University of Science and Technology;College of Materials Science and Engineering, Beijing University of Technology;Department of Mechanical Engineering, University of South Florida, United States of America

关键词: Electrical contact;    Al2O3 nanoparticles;    orientation relationship;    mass transfer mechanism;   

DOI  :  10.1515/ntrev-2019-0012

学科分类：社会科学、人文和艺术（综合）

来源: De Gruyter

【 摘 要 】

In order to investigate the effects of chromium on the electrical contact properties of the Al 2 O 3 -Cu/15W composites, vacuum hot-pressing sintering and internal oxidation methods were employed to fabricate the Al 2 O 3 -Cu/15W and Al 2 O 3 -Cu/15W5Cr composites. The microstructure was analyzed by scanning and transmission electron microscopy. The electrical contacts testing was performed using the JF04C testing machine at 30 V DC with 10-30 A current. The effects of Cr on the comprehensive properties, arc erosion morphology and welding force of the electrical contacts were investigated. The mass transfer mechanism was discussed. It was demonstrated that the Al 2 O 3 nanoparticles pinned dislocations. The diffraction spots of the Cu matrix and the γ -Al2O3 disclose an orientation relationship of Cu // γ −Al2O3 ,{020} Cu //{040} γ −Al2O3 . A typical arc erosion morphology, such as needle-like and coral structures was formed, which provides significantly enhanced arc erosion resistance of the contact material. Compared with the Al 2 O 3 -Cu/15W composite, the Al 2 O 3 -Cu/15W5Cr composite has a lower welding force. The two composites present two distinct mass transfer trends before and after 25 A. The final mass transfer direction of the composites is from the cathode to the anode. The Al 2 O 3 -Cu/15W5Cr contacts have less mass change under all testing conditions.

【 授权许可】

CC BY