Micro-manufacturing of micro-scale porous surface structures for enhanced heat transfer applications: an experimental process optimization study (original) (raw)
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Fabrication of High Aspect Ratio Porous Microfeatures Using Hot Compaction Technique
2008
High aspect ratio porous microfeatures are becoming more important in the modern industry. However, the fabrication of such features under a mass production environment remains a challenge when robustness, cost effectiveness, and high productivity requirements are required. In this study, the forming of such porous microfeatures using hot compaction was investigated. A hot compaction experimental setup was designed and fabricated that is capable of performing high temperature operation (700°C), quick heatup, and avoiding oxidation. 3D thermal simulation of the experimental setup was conducted to investigate the heat transfer performance and internal temperature distribution, which was then used as a reference for the experiment. Hot compaction experiments were carried out, and the effects of compression force and temperature on the quality in terms of powder consolidation strength and porosity were investigated. In addition, the achievable aspect ratio and taper angle were also discussed.
Journal of Alloys and Compounds, 2009
The present article describes the process of Self-propagating High-temperature Synthesis (SHS) that is employed for fabricating open cell copper-alumina composite foam. This foam was fabricated by the reactions between the powders of CuO, Al and C. The gas released during these reactions as well as the initial porosity of the green powder compact were suggested to be the sources of the produced pores. Further, the effect of C content and the precursor compressing pressure on the porosity content and morphology of the SHS product was determined. Optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) were utilized to characterize the porous samples. The optimum weight fractions for blending the initial powders were determined to be 84 wt.% CuO, 9.5 wt.% Al, and 6.5 wt.% C, and the SHS reaction was sustainable only if the initial compacting pressure of the powders was between 100 and 300 MPa.
Applied Thermal Engineering, 2019
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Fabrication and thermo-mechanical behavior of ultra-fine porous copper
Journal of Material Science, 2014
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