Chun-Nian He
,
Chao Feng
,
Ji-Chuan Lin
,
En-Zuo Liu
,
Chun-Sheng Shi
,
Jia-Jun Li
,
Nai-Qin Zhao
金属学报(英文版)
doi:10.1007/s40195-016-0376-3
Carbon nanotube (CNT)-reinforced 6061Al alloy matrix composites were prepared by chemical vapor deposition (CVD) combined with hot extrusion technique. During the preparation process, the 6061Al flakes obtained by ball milling of the 6061Al spherical powders were subjected to surface modification to introduce a hydrophilic polyvinyl alcohol (PVA) membrane on their surface (6061Al@PVA) to bond strongly with nickel acetate [Ni(II)]. Then the 6061Al@PVA flakes bonded with Ni(II) were calcined and reduced to Ni nanoparticles, which were then heat-treated at 580 °C to remove PVA for obtaining even Ni/6061Al catalyst. After that, the as-obtained Ni/6061Al catalyst was employed to synthesize CNTs on the surface of the 6061Al flakes by CVD. After hot extrusion of the CNT/6061Al composite powders, the as-obtained CNT/6061Al bulk composites with 2.26 wt% CNTs exhibited 135% increase in yield strength and 84.5% increase in tensile strength compared to pristine 6061Al matrix.
关键词:
Metal
,
matrix
,
composites
,
(MMCs)
,
Microstructure
,
Mechanical
,
properties
,
Carbon
Z.Z. Yang
,
W. Tian
,
Q.R. Ma
,
null
,
null
,
null
,
null
,
null
,
null
,
null
,
null
金属学报(英文版)
Since the development of offshore oil and gas, the increased submarine oil and gas pipelines were installed. All the early steel pipes of submarine pipeline were depended on importing because of the strict requirements of comprehensive properties such as anti-corrosion, resistance to pressure and so on. In order to research and develop domestic steel pipe used for submarine pipeline, the Longitudinal-seam Submerged Arc Welded (LSAW) pipes were made of steel plates cut from the levelled steel rolls by both JCOE and UOE forming process. And the mechanical properties of the pipe base metal and weld metal were tested, the results were in accord with the corresponding pipe specification API SPEC 5L or DNV-OS-F101, which showed the domestic LSAW pipes could be used to the submarine oil and gas pipeline.
关键词:
Mechanical Properties
,
Properties
,
Offshore
,
oil
,
and
,
g
Zhaoxia PING
金属学报(英文版)
Ni-P-SiC composite coatings were electroplated on carbon steel substrate assisted by mechanical attrition (MA). The MA action was conducted by dispersing glass balls on the cathodic surface, vibrating in the horizontal direction. The experimental results show that, under the assistant of MA action, the adhesion of Ni-P-SiC coating on the steel substrate can be improved effectively, and the Ni-P-SiC coatings exhibit a crystallized structure and Ni-P matrix can combine tightly with SiC particles, and the hardness and corrosion resistance of these coatings increase markedly. During heat treatment, the defects produced in conventional Ni-P-SiC composite coatings can be avoided assisted by MA action. Both of the wear resistance and corrosion resistance of these coatings can be improved further.
关键词:
Ni-P-SiC composite coating
,
electroplating
,
mechanical attrition
