Densification and microstructural evolution during laser sintering of A356/SiC composite powders |
| |
| Authors: | A Simchi D Godlinski |
| |
| Affiliation: | (1) Department of Materials Science and Engineering, Sharif University of Technology, Azadi Avenue, P.O. Box 11365-9466, 14588 Tehran, Iran;(2) Institute for Nanoscience and Nanotechnology (INST), Sharif University of Technology, Azadi Avenue, P.O. Box 11365-9466, 14588 Tehran, Iran;(3) Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM, Wiener Str. 12, 28359 Bremen, Germany |
| |
| Abstract: | This article reports experimental results on laser sintering of A356 aluminum alloy and A356/SiC composite powders. Effects
of scan rate, sintering atmosphere, hatch spacing, and SiC volume fraction (up to 20%), and particle size (7 and 17 μm) on
the densification were studied. The phase formation and microstructural development were analyzed by X-ray diffraction (XRD)
and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS). Laser sintering under argon
atmosphere exhibited higher densification compared to nitrogen. A faster sintering kinetics was observed as the scan rate
decreased. Except at a low SiC content (5 vol%), the composite powders exhibited lower densification kinetics. The densification
was improved when finer SiC particles were utilized. Microstructural studies revealed directional solidification of aluminum
melt to form columnar grains with inter-columnar silicon precipitates. In the presence of SiC particles, aluminum melt reacted
with the ceramic particles to form Al4SiC4 plates. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
