Partial Wetting of Aqueous Solutions on High Aspect Ratio Nanopillars with Hydrophilic Surface Finish

2014 ◽  
Vol 3 (1) ◽  
pp. N3095-N3100 ◽  
Author(s):  
G. Vereecke ◽  
XiuMei Xu ◽  
W. K. Tsai ◽  
Hui Yang ◽  
S. Armini ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Aqueous Solutions ◽  
Surface Finish ◽  
High Aspect Ratio ◽  
Hydrophilic Surface ◽  
Partial Wetting

(Invited) Wetting Behavior of Aqueous Solutions on High Aspect Ratio Nanopillars with Hydrophilic Surface Finish

2013 ◽  
Vol 58 (6) ◽  
pp. 171-182 ◽  
Author(s):  
G. Vereecke ◽  
X. Xu ◽  
W.-K. Tsai ◽  
H. Yang ◽  
S. Armini ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Aqueous Solutions ◽  
Surface Finish ◽  
High Aspect Ratio ◽  
Hydrophilic Surface ◽  
Wetting Behavior

Boehmite Nanofibers as a Dispersant for Nanotubes in an Aqueous Sol

2018 ◽  
Author(s):  
Gen Hayase
Keyword(s):  
Carbon Nanotubes ◽  
Aspect Ratio ◽  
Aqueous Solutions ◽  
High Aspect Ratio ◽  
Multiwall Carbon Nanotubes ◽  
Multiwall Carbon ◽  
Nanotube Films

By exploiting the dispersibility and rigidity of boehmite nanofibers (BNFs) with a high aspect ratio of 4 nm in diameter and several micrometers in length, multiwall-carbon nanotubes (MWCNTs) were successfully dispersed in aqueous solutions. In these sols, the MWCNTs were dispersed at a ratio of about 5–8% relative to BNFs. Self-standing BNF–nanotube films were also obtained by filtering these dispersions and showing their functionality. These films can be expected to be applied to sensing materials.

High Aspect Ratio Micro-EDM Drilling with Nano Surface Finish

2016 ◽  
pp. 157-164
Author(s):  
Mohammad Yeakub Ali ◽  
Mohamed Abd Rahman ◽  
Asfana Banu ◽  
Shakira Adnan ◽  
Fatin Nadia
Keyword(s):  
Aspect Ratio ◽  
Surface Finish ◽  
High Aspect Ratio ◽  
Micro Edm ◽  
Edm Drilling

Machining of High Aspect Ratio Micro-Holes on Titanium Alloy Using Silver Nano Powder Mixed Micro EDM Drilling

2019 ◽  
Author(s):  
Chong Liu ◽  
Asif Rashid ◽  
Muhammad P. Jahan ◽  
Jianfeng Ma
Keyword(s):  
Titanium Alloy ◽  
Aspect Ratio ◽  
Surface Finish ◽  
High Aspect Ratio ◽  
Electrical Discharge Machining ◽  
Turbine Blades ◽  
Weight Ratio ◽  
Recast Layer ◽  
Micro Edm ◽  
Micro Holes

Abstract Titanium alloy Ti-6Al-4V is used extensively in aerospace engines because of its high strength-to-weight ratio and corrosion resistance. Machining of cooling holes in turbine blades for aerospace engines is one of the major challenges faced in aerospace industries. Ti-6Al-4V is known as a difficult to be machined material by conventional machining processes, and machining of micro-through-holes with diameter less than 100 microns is even more challenging. Therefore, the objective of this study is to investigate the feasibility of machining high aspect ratio micro-through holes in Ti-6Al-4V using micro electrical discharge machining (micro-EDM) with the silver (Ag) nanopowder mixed dielectric. The machining time, overcut, recast layer, crater size, aspect ratio and surface finish of the micro-holes were evaluated. In order to minimize the positional inaccuracy and spindle runout, the microelectrodes were fabricated in-situ using block micro-EDM process. In this study, as received electrode of 300 microns diameter tungsten wire was reduced to about 50 microns diameter rod by micro block EDM using a tungsten carbide block. The effect of powder concentration, gap voltage, capacitance and electrode rotational speed was studied. It is found that high quality micro-holes of about 50 microns diameter can be achieved successfully and repeatedly using powder mixed micro-EDM (PM-μEDM). The micro-holes generated by PM-μEDM provides comparatively smoother surface finish and minimal recast layer around the rim of the micro-holes. In addition, PM-μEDM process improves machining stability, thus allowing to minimize the hole size and quality, thus enhancing the aspect ratio of micro-holes.

Boehmite Nanofibers as a Dispersant for Nanotubes in an Aqueous Sol

2018 ◽  
Author(s):  
Gen Hayase
Keyword(s):  
Carbon Nanotubes ◽  
Aspect Ratio ◽  
Aqueous Solutions ◽  
High Aspect Ratio ◽  
Multiwall Carbon Nanotubes ◽  
Multiwall Carbon ◽  
Nanotube Films

By exploiting the dispersibility and rigidity of boehmite nanofibers (BNFs) with a high aspect ratio of 4 nm in diameter and several micrometers in length, multiwall-carbon nanotubes (MWCNTs) were successfully dispersed in aqueous solutions. In these sols, the MWCNTs were dispersed at a ratio of about 5–8% relative to BNFs. Self-standing BNF–nanotube films were also obtained by filtering these dispersions and showing their functionality. These films can be expected to be applied to sensing materials.

scholarly journals Debinding and Presintering of High Aspect Ratio Microbi-Lumen Tubes Produced by Extrusion of 17-4PH Feedstock

2020 ◽  
Vol 8 (2) ◽  
Author(s):  
Sandeep Kuriakose ◽  
Salvatore Cataldo ◽  
Paolo Parenti ◽  
Massimiliano Annoni
Keyword(s):  
Aspect Ratio ◽  
Structural Properties ◽  
Surface Finish ◽  
High Aspect Ratio ◽  
Three Dimensional ◽  
Processing Technologies ◽  
Green State ◽  
Aspect Ratios ◽  
Recent Developments ◽  
Thermal Debinding

Abstract Recent developments have showcased that micro-extrusion of feedstock can be used for manufacturing metallic microbi-lumen tubes with very high length-to-diameter aspect ratios, which are not viable by conventional metal extrusion or commonly used feedstock processing technologies like injection molding or hot pressing. The extrusion of high aspect ratio microcomponents faces the challenge of maintaining the geometrical accuracy, surface finish, and structural properties since the micro-extrusion in green state is followed by debinding and sintering operations, which result in shrinkage and variations in surface finish and structure. The stages of the process chain such as solvent/thermal debinding (TD), to remove the polymeric binder, and presintering (PS), to achieve a mild structural rigidity before the sintering, are of critical importance to achieve the surface and structural properties of high aspect ratio microparts and have not been yet studied in case of micro-extrusion of feedstock. In this study, the effect of debinding and PS on surface and structural properties of bi-lumen tubes processed at different extrusion conditions is discussed. Surface roughness of the tubes is analyzed using three-dimensional microscopy, and structural properties are studied using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The debinding and PS experiments on extruded microbi-lumen tubes retained very good surfaces integrity without any cracks or defects. The study shows that the interactions of extrusion temperature and extrusion velocity influence the surface finish of the extruded tubes the most. The sintered bi-lumen samples showed a good areal surface finish, Sa of 2.21 μm, which is near to the green state value confirming the suitability of the applied debinding and PS parameters.

Creating Metal Molds for Directional Gecko-Inspired Adhesives

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Capella Kerst ◽  
Srinivasan A. Suresh ◽  
Mark R. Cutkosky
Keyword(s):  
Shear Stress ◽  
Aspect Ratio ◽  
Surface Finish ◽  
High Aspect Ratio ◽  
Smooth Surface ◽  
Metal Mold ◽  
Dry Adhesives ◽  
Single Use

Abstract We describe a process for creating durable metal molds for the fabrication of directional, gecko-inspired dry adhesives. The adhesives require microscopic inclined features with a challenging combination of tapered geometry, high aspect ratio, and smooth surface finish. Wedge-shaped features produced by the new metal mold exhibit the same geometry and surface finish as those cast from single-use wax molds and epoxy molds in previous fabrication methods. They also produce the same levels of adhesion and shear stress. The metal molds, and the adhesives cast from them, show no degradation after repeated molding cycles.

Boehmite Nanofibers as a Dispersant for Nanotubes in an Aqueous Sol

2018 ◽  
Author(s):  
Gen Hayase
Keyword(s):  
Carbon Nanotubes ◽  
Aspect Ratio ◽  
Aqueous Solutions ◽  
High Aspect Ratio ◽  
Multiwall Carbon Nanotubes ◽  
Multiwall Carbon ◽  
Nanotube Films

By exploiting the dispersibility and rigidity of boehmite nanofibers (BNFs) with a high aspect ratio of 4 nm in diameter and several micrometers in length, multiwall-carbon nanotubes (MWCNTs) were successfully dispersed in aqueous solutions. In these sols, the MWCNTs were dispersed at a ratio of about 5–8% relative to BNFs. Self-standing BNF–nanotube films were also obtained by filtering these dispersions and showing their functionality. These films can be expected to be applied to sensing materials.

Sign in / Sign up

Export Citation Format

Share Document