Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1689763 | Vacuum | 2015 | 8 Pages |
Abstract
Amorphous Ni53Nb20Ti10Zr8Co6Ta3 powders were successfully fabricated by mechanical alloying. The glass-forming ability and crystallization behavior of the synthesized alloy powders were investigated by X-ray diffraction, transmission electron microscopy and differential scanning calorimetry. The non-isothermal crystallization kinetics were analyzed by the Johnson-Mehl-Avrami equation. The crystallization of the amorphous Ni53Nb20Ti10Zr8Co6Ta3 powders exhibits two distinct steps, and the values of the Avrami exponent n implies that the crystallization of the first and second steps are dominated by interface-controlled three-dimensional growth as well as the volume-diffusion-controlled two-dimensional growth, respectively. In addition, the bulk crystallized alloys consolidated from the amorphous powders by spark plasma sintering exhibit high fracture strength of 3169Â MPa and ultra-high hardness of 1069Â HV. The compressive fracture strength and fracture strain of the as sintered alloy at 1073Â K reach 2020Â MPa and 7.6%, respectively.
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
Xiaoqiang Li, Zhun Cheng, Ke Hu, Huojin Chen, Chao Yang,