Search

Your search keyword '"Fu Hengzhi"' showing total 1,624 results
Start Over Author "Fu Hengzhi"
1,624 results on '"Fu Hengzhi"'

2. Study on in situ Al-Si functionally graded materials produced by traveling magnetic field

Author

Xu Yanjin, Su Yanqing, Luo Liangshun, Liu Jiangping, Guo Jingjie, and Fu Hengzhi

Subjects
aluminum alloys, composites, microstructure, traveling magnetic field, Materials of engineering and construction. Mechanics of materials, TA401-492
Abstract

The aim of this contribution was to investigate the microstructure of in situ Al-Si functionally graded materials produced by traveling magnetic field. The research shows that the composition and associated microstructural feature of Al-Si alloys processed by this method changes from the outer of samples to the inner, respectively, from Al-Si hypereutectic with particles of primary Si to Al-Si eutectic to hypoeutectic composition with a great number of primary Al dendrites. Moreover, the hardness, the wear resistance of samples and the volume fraction of primary Si particles all have obviously gradient characteristics in the samples.

Published
2012
Full Text
View/download PDF

3. Effect of cooling rate on MC carbide in directionally solidified nickel-based superalloy under high thermal gradient

Author

Zhang Weiguo, Liu Lin, and Fu Hengzhi

Subjects
directional solidification, cooling rate, nickel-based superalloy, MC carbide, Technology, Manufactures, TS1-2301
Abstract

A series of directional solidification experiments have been performed to study the effect of cooling rate on the precipitation behavior of MC carbide in nickel-based superalloy under the temperature gradient of 500 K·s-1. Results reveal that the morphology of MC carbide changes from coarse block to fine strip, then to Chinese-script, and their sizes reduce gradually with the increasing of cooling rate from 2.53 K·s-1 to 36.4 K·s-1. At low cooling rates, most of these carbides are found to be located at the grain boundary and interdendritic regions, while the coupled growth of some carbides and γ matrix in the center of γ grains is occurred at high cooling rate. The main elements forming MC carbide are Ta, W, and Hf.

Published
2012

4. Based on database and asp.net technologies, a web platform of scientific data in the casting forces on the mold-fi lling behavior of titanium melts in vertically rotating molds

Author

Xu Daming, Fu Hengzhi, and Jia Limin

Subjects
centrifugal casting, Coriolis force, mold-fi lling, solidifi cation-heat transfer, computer simulation, Technology, Manufactures, TS1-2301
Abstract

The vertical centrifugal-casting technique is widely used in the manufacture of various irregularlyshaped castings of advanced structural alloys with thin walls, complex shapes and/or large sizes. These castings are used in the increasing applications in aero-space/aviation industries, human teeth/bone repairs with nearnet shaped components, etc. In a vertically rotating casting system, the mold-filling processes of alloy melts, coupled with solidifi cation-heat transfer, may be much more complicated, because they are driven simultaneously by gravity, centrifugal and Coriolis forces. In the present work, an N-S/VOF-equations-based model, solved using a SOLA-VOF algorithm, under a rotating coordinate system was applied to numerically investigate the impacts of centrifugal and Coriolis forces on metallic melt mold-fi lling processes in different vertical centrifugal-casting configurations with different mold-rotation rates using an authors’ computer-codes system. The computational results show that the Coriolis force may cause remarkable variations in the fl ow patterns in the casting-part-cavities of a large horizontal-section area and directly connected to the sprue via a short ingate in a vertical centrifugalcasting process. A “turn-back” mold-filling technique, which only takes advantage of the centrifugal force in a transient rotating melt system, has been confi rmed to be a rational centrifugal-casting process in order to achieve smooth and layer-by-layer casting-cavities-fi lling control. The simulated mold-fi lling processes of Ti-6Al-4V alloy melt, in a vertical centrifugal-casting system with horizontally-connected plate-casting cavities, show reasonable agreement with experimental results from the literature.

Published
2008

Catalog

Books, media, physical & digital resources
See catalog results