scholarly journals Morphological Development of Sub-Grain Cellular/Bands Microstructures in Selective Laser Melting

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1204 ◽  
Author(s):  
Xihe Liu ◽  
Xin Zhou ◽  
Ben Xu ◽  
Jing Ma ◽  
Congcong Zhao ◽  
...  
Keyword(s):  
Surface Tension ◽  
Selective Laser Melting ◽  
Single Layer ◽  
Liquid Interface ◽  
Morphological Development ◽  
Eutectic Alloys ◽  
Laser Melting ◽  
Submicron Scale ◽  
Solid Liquid Interface ◽  
Solid Liquid

In this paper, single-layer and bulk 316 L selective laser melting (SLM) experiments were conducted, fine submicron-scale geometric symmetrical cellular (hexagonal, pentagonal and square), elongated cellular and bands solidification morphologies were found in the laser-melt top surface. Meanwhile, morphological developed sub-grain patterns with quasi-hexagonal cellular, elongated cellular and bands structures (size ~1 μm) coexisting inside one single macro-solidified grain were also identified. This demonstrated the transitions from quasi-hexagonal-cells to elongated cells/bands, and transitions reverse, occurred in the whole bulk under some circumstances during SLM. Based on the experimental realities, these morphologies are formed by the local convection and Bénard instabilities in front of the solid/liquid interface (so-called mushy zones) affected by intricate temperature and surface tension gradients. Quasi-hexagonal cellular convective fields are then superimposed on macro-grain solidification to form the sub-grain patterns and micro-segregations. This explanation seems reasonable and is unifying as it can be expanded to other eutectic alloys with face center cubic (FCC) prevenient phase prepared by SLM, e.g., the Al-Si and Co-Cr-Mo systems.

Surface tension of liquid Al-Cu and wetting at the Cu/Sapphire solid-liquid interface

2014 ◽  
Vol 223 (3) ◽  
pp. 469-479 ◽  
Author(s):  
J. Schmitz ◽  
J. Brillo ◽  
I. Egry
Keyword(s):  
Surface Tension ◽  
Liquid Interface ◽  
Solid Liquid Interface ◽  
Solid Liquid

The validity of Antonow's rule for the solid-liquid interface, and the consequent measurement of the surface-tension of solids

Physica ◽  
1934 ◽  
Vol 1 (7-12) ◽  
pp. 1181-1201 ◽  
Author(s):  
R. Loman ◽  
N.P. Zwikker
Keyword(s):  
Surface Tension ◽  
Liquid Interface ◽  
Solid Liquid Interface ◽  
Solid Liquid

Dependence of the Contact Angle on Adsorption at the Solid-Liquid Interface

2010 ◽  
Author(s):  
C. A. Ward
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Pressure Range ◽  
Line Tension ◽  
Liquid Interface ◽  
Fluid Interfaces ◽  
Phase Line ◽  
Three Phase ◽  
Solid Liquid Interface ◽  
Solid Liquid

A method for determining the surface tension of solid-fluid interfaces has been proposed. For a given temperature and fluid-solid combination, these surface tensions are expressed in terms of material properties that can be determined by measuring the amount of vapor adsorbed on the solid surface as a function of xV, the ratio of the vapor-phase pressure to the saturation-vapor pressure. The thermodynamic concept of pressure is shown to be in conflict with that of continuum mechanics, but is supported experimentally. This approach leads to the prediction that the contact angle, θ, can only exist in a narrow pressure range and that in this pressure range, the solid-vapor surface tension is constant and equal to the surface tension of the liquid-vapor interface, γLV. The surface tension of the solid-liquid interface, γSL, may be expressed in terms of measurable properties, γLV and θ: γSL = γLV(1 − cosθ). The value of θ is predicted to depend on both the pressure in the liquid at the three-phase, line x3L, and the three-phase line curvature, Ccl. We examine these predictions using sessile water droplets on a polished Cu surface, maintained in a closed, constant volume, isothermal container. The value of θ is found to depend on the adsorption at the solid-liquid interface, nSL = nSL(x3L,Ccl). The predicted value of θ is compared with that measured, and found to be in close agreement, but no effect of line tension is found.

The surface tension in a structural model for the solid-liquid interface

1976 ◽  
Vol 10 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Frans Spaepen ◽  
Robert B. Meyer
Keyword(s):  
Surface Tension ◽  
Structural Model ◽  
Liquid Interface ◽  
Solid Liquid Interface ◽  
Solid Liquid

Molecular dynamics study of thermal resistance of solid-liquid interface in contact with single layer of nanoparticles

2018 ◽  
Vol 120 ◽  
pp. 608-623 ◽  
Author(s):  
Yoshitaka Ueki ◽  
Yasuhiro Miyazaki ◽  
Masahiko Shibahara ◽  
Taku Ohara
Keyword(s):  
Molecular Dynamics ◽  
Thermal Resistance ◽  
Single Layer ◽  
Liquid Interface ◽  
Solid Liquid Interface ◽  
Solid Liquid

scholarly journals The impact of grafted surface defects on the on-surface Schiff-base chemistry at the solid–liquid interface

2018 ◽  
Vol 54 (71) ◽  
pp. 9905-9908 ◽  
Author(s):  
Nerea Bilbao ◽  
Yanxia Yu ◽  
Lander Verstraete ◽  
Jianbin Lin ◽  
Shengbin Lei ◽  
...  
Keyword(s):  
Schiff Base ◽  
Surface Defects ◽  
Single Layer ◽  
Liquid Interface ◽  
Covalent Organic Frameworks ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
The Impact

We investigate the effect of covalently modified graphitic surfaces on the formation of single-layer covalent organic frameworks (sCOFs) at the solid–liquid interface.

The surface tension in a structural model for the solid-liquid interface

1976 ◽  
Vol 10 (3) ◽  
pp. 257-263 ◽  
Author(s):  
Frans Spaepen ◽  
Robert B. Meyer
Keyword(s):  
Surface Tension ◽  
Structural Model ◽  
Liquid Interface ◽  
Solid Liquid Interface ◽  
Solid Liquid

Mechanisms of porosity formation along the solid/liquid interface during laser melting of ceramics

2003 ◽  
Vol 208-209 ◽  
pp. 458-462 ◽  
Author(s):  
D. Triantafyllidis ◽  
L. Li ◽  
F.H. Stott
Keyword(s):  
Liquid Interface ◽  
Laser Melting ◽  
Porosity Formation ◽  
Solid Liquid Interface ◽  
Solid Liquid

In-Line Characterization of Micro-Droplets Based on Partial Light Reflection at the Solid-Liquid Interface

2012 ◽  
Author(s):  
Emanuel Weber ◽  
Dietmar Puchberger-Enengl ◽  
Michael J. Vellekoop
Keyword(s):  
Optical Properties ◽  
Single Layer ◽  
Cost Effective ◽  
Continuous Phase ◽  
Liquid Interface ◽  
Transmitted Light ◽  
Index Of Refraction ◽  
Light Reflection ◽  
Solid Liquid Interface ◽  
Solid Liquid

In this paper a novel optofluidic setup, fabricated on a single layer device for in-line droplet characterization yielding droplet-size, droplet-frequency, and optical properties with compatibility for full on-chip integration is presented. Chips were fabricated using a simple, fast, and cost effective technology. A T-junction arrangement on the device is used for droplet generation. The optical part of the setup consists of an external light source, external silicon photodetectors, integrated air micro-lenses, and an integrated waveguide. The design makes use of partial light reflection/transmission at the solid-liquid interface to count, size, and discriminate droplets based on their optical properties. When passing the interrogation point, droplets having a lower refractive index as the continuous phase result in light deflections. Both, reflected and transmitted light, are detected simultaneously. A relation of those two signals is then used for the analysis resulting in a continuously stable signal. The generated pattern is unique for different droplets and can be exploited for droplet characterization. Using this arrangement, droplets of de-ionized water (DI) were counted at frequencies of up to 320 droplets per second. In addition, information about the droplet sizes and their variations could be obtained. Finally, 5 mol/L CaCl2 and DI droplets, having different indices of refraction were examined and could clearly be discriminated based on their unique reflected and transmitted light signals. This principle can be applied for the detection of dissolved molecules in droplets as long as they influence the index of refraction. Examples could be the determination of DNA or protein content in the droplet.

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