scholarly journals Laser Fabrication of Titanium Alloy-Based Photothermal Responsive Slippery Surface

2022 ◽  
Vol 12 (2) ◽  
pp. 608
Author(s):  
Jian Yi ◽  
Hao Zhou ◽  
Xingchen Han ◽  
Jiangwei Mao ◽  
Yonglai Zhang
Keyword(s):  
Titanium Alloy ◽  
Substrate Surface ◽  
Light Response ◽  
Liquid Droplets ◽  
Metallic Surfaces ◽  
Important Research Topic ◽  
Butterfly Wings ◽  
Slippery Surface ◽  
High Absorption ◽  
Smart Surface

In recent years, biomimetic materials inspired from natural organisms have attracted great attention due to their promising functionalities and cutting-edge applications, emerging as an important research topic. For example, how to reduce the reflectivity of the solid surface and increase the absorption of the substrate surface is essential for developing light response smart surface. Suitable solutions to this issue can be found in natural creatures; however, it is technologically challenging. In this work, inspired from butterfly wings, we proposed a laser processing technology to prepare micro nanostructured titanium alloy surfaces with anti-reflection properties. The reflectivity is significantly suppressed, and thus, the light absorption is improved. Consequently, the anti-reflection titanium alloy surface can be further employed as a photothermal substrate for developing light-responsive slippery surface. The sliding behavior of liquid droplets on the smart slippery surface can be well controlled via light irradiation. This method facilitates the preparation of low-reflection and high-absorption metallic surfaces towards bionic applications.

Biocompatible Ceramic-Biopolymer Coatings Obtained by Electrophoretic Deposition on Electron Beam Structured Titanium Alloy Surfaces

2016 ◽  
Vol 879 ◽  
pp. 1552-1557
Author(s):  
C. Ramskogler ◽  
L. Cordero ◽  
Fernando Warchomicka ◽  
A.R. Boccaccini ◽  
Christof Sommitsch
Keyword(s):  
Titanium Alloy ◽  
Surface Modification ◽  
Electron Beam ◽  
Electrophoretic Deposition ◽  
Composite Coatings ◽  
Substrate Surface ◽  
3D Structure ◽  
Titania Nanoparticles ◽  
Structured Surfaces ◽  
Major Interest

An area of major interest in biomedical engineering is currently the development of improved materials for medical implants. Research efforts are being focused on the investigation of surface modification methods for metallic prostheses due to the fundamental bioinert character of these materials and the possible ion release from their surfaces, which could potentially induce the interfacial loosening of devices after implantation. Electron beam (EB) structuring is a novel technique to control the surface topography in metals. Electrophoretic deposition (EPD) offers the feasibility to deposit at room temperature a variety of materials on conductive substrates from colloidal suspensions under electric fields. In this work single layers of chitosan composite coatings containing titania nanoparticles (n-TiO2) were deposit by EPD on electron beam (EB) structured Ti6Al4V titanium alloy. Surface structures were designed following different criteria in order to develop specific topography on the Ti6Al4V substrate. n-TiO2 particles were used as a model particle in order to demonstrate the versatility of the proposed technique for achieving homogenous chitosan based coatings on structured surfaces. A linear relation between EPD time and deposition yield on different patterned Ti6Al4V surfaces was determined under constant voltage conditions, obtaining homogeneous EPD coatings which replicate the 3D structure (pattern) of the substrate surface. The present results show that a combination of both techniques can be considered a promising surface modification approach for metallic implants, which should lead to improved interaction between the implant surface and the biological environment for orthopaedic applications.

scholarly journals Coalescence of droplets on micro-structure patterned hydrophobic planar solid surfaces

RSC Advances ◽  
2017 ◽  
Vol 7 (39) ◽  
pp. 23954-23960 ◽  
Author(s):  
Guiping Zhu ◽  
Hui Fan ◽  
Hulin Huang ◽  
Fei Duan
Keyword(s):  
Surface Properties ◽  
Substrate Surface ◽  
Solid Surfaces ◽  
Liquid Droplets ◽  
Micro Structure

The motion and coalescence of sessile liquid droplets on patterned solid surfaces are investigated systematically in terms of the liquid and substrate surface properties.

scholarly journals TECHNOLOGY FOR RESTORATION AND REPAIR OF AIRCRAFT ENGINE PARTS

Aviation ◽  
2021 ◽  
Vol 25 (4) ◽  
pp. 262-267
Author(s):  
Serhii Nyzhnyk ◽  
Ihor Zorik ◽  
Kostiantyn Danko ◽  
Justas Nugaras
Keyword(s):  
Titanium Alloy ◽  
Substrate Surface ◽  
Aircraft Engine ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Technological Parameters ◽  
Detonation Spraying ◽  
Compressor Blades ◽  
Complex Technology ◽  
Spraying Process

Problems of increasing the service life of compressor blades of aircraft gas turbine engines using detonation spraying technology are considered. The simulation of the parameters of the velocity and temperature of the particles of the sprayed material in the barrel of the detonation unit and in the flooded space to the substrate was carried out, followed by the choice of the optimal technological parameters of the spraying process. The control system of the detonation unit has been modernized. An experiment was carried out on the deposition of the Al2O3 coatings on the samples of a substrate made of titanium alloy VT3-1. Based on the results of the experiment, technological recommendations were developed concerning both the parameters of the spraying process and the parameters of the preparation of the substrate surface before spraying. The equipment for brazing the blades of the guide vanes is described and a device for spraying coatings on the end surfaces of the compressor blades is proposed. Thus, a complex technology has been developed for restoring the end surfaces of titanium alloy compressor blades by deposition of Al2O3 coatings.

Study on TiCN/Ti Based Composite Coating Fabricated by Reactive Electric Spark Deposition

2012 ◽  
Vol 190-191 ◽  
pp. 567-570
Author(s):  
Jian Jun Hao ◽  
Liang Gao ◽  
Shu Hua Yang ◽  
Xiong Zhuang Li ◽  
Yue Jin Ma
Keyword(s):  
Titanium Alloy ◽  
Composite Coating ◽  
Graphite Electrode ◽  
Substrate Surface ◽  
Alloy Surface ◽  
Interfacial Behavior ◽  
Nitrogen Gas ◽  
Hardness Tester ◽  
Tc4 Titanium Alloy ◽  
Microhardness Profile

In order to improve the wear-resisting properties of titanium alloy surface, reactive electric spark deposition was carried out using a graphite electrode in a nitrogen gas atmosphere, and TiCN/Ti based composite coating was fabricated on TC4 titanium alloy surface. The surface morphology, microstructure, interfacial behavior between the coatings and substrate, phase and element composition of the coatings were investigated by scanning electron microscope（SEM), X-ray diffraction (XRD) and Auger electron spectroscopy (AES). The microhardness hardness distributions as a function of depth were measured by a micro-hardness tester. The results show that the coating about 20μm thick is continuous, close, and completely covering the substrate surface and mainly composed of the TiCN phase which is in-situ synthesized by the reaction among titanium from the substrate, carbon from the graphite electrode and nitrogen from the shielding nitrogen gas. The coating has a strong metallurgical bonding and adhesion to the substrate. Microhardness profile falls off with the coatings thickness increasing and the highest microhardness values of the superficial coating could be up to 1496HV, which is six times more than that of the substrate.

Effect of Pickling Process on Adhesion Strength of Ti Oxide Layer on Titanium Alloy Substrate

2010 ◽  
Vol 146-147 ◽  
pp. 1621-1630 ◽  
Author(s):  
Sudin Izman ◽  
Mohammed Rafiq Abdul Kadir ◽  
Mahmood Anwar ◽  
Engku Mohammad Nazim ◽  
Low Yik Kuan ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
Oxide Layer ◽  
Adhesion Strength ◽  
Biomedical Application ◽  
Substrate Surface ◽  
Wear Properties ◽  
Aqueous Acid ◽  
Pickling Solution ◽  
Pickling Process ◽  
Titanium Alloy Substrate

Titanium alloys are commonly used in biomedical application in hard tissues replacement especially for knee and hip implants. Surface modifications are required prior to diamond coating process for improving the tribological and wear properties of the titanium alloy. In this study, experiments were carried out to investigate the effects of different pickling times as well as temperature on the adhesion strength of oxide layer formed on the Titanium alloy after oxidation process. The aqueous acid solution of HF and HNO3 was used as a pickling solution. The chemical pretreatment was carried out at 4 levels by varying the pickling time as well as temperature. All treated samples were thermally oxidized in a fixed parameters at 900 °C for 25 hours. Surface morphology, oxide layer thickness and adhesion strength were measured after each step using FESEM and Blast Wear Tester (BWT). It was revealed that the thickness of oxide layer increases with pickling time but the adhesion strengths become weaker. It was also found that the adhesion strength of oxide layer formed on Ti substrate surface increases with the increase of temperature while the thickness of the oxide layer decreased within 40oC pickling temperature.

Jet Initiation After Drop Impact on Micropatterned Hydrophilic Surfaces

2019 ◽  
Author(s):  
Anayet Ullah Siddique ◽  
Feng Zhao ◽  
Mark Weislogel ◽  
Hua Tan
Keyword(s):  
High Speed ◽  
Dynamic Properties ◽  
Substrate Surface ◽  
Droplet Diameter ◽  
Drop Impact ◽  
Liquid Droplets ◽  
Jet Formation ◽  
Lift Off ◽  
Micro Pillars ◽  
Jet Initiation

Abstract Droplet-wall impacts are well known to produce a wide variety of outcomes such as spreading, splashing, jetting, receding, and rebounding from hydrophobic and superhydrophobic surfaces. In this work, we focus on the growth of jets that form during the partial recoil of liquid droplets that impinge upon hydrophilic substrates composed of cylindrical micro-pillars of various dimensions and distributions (i.e., height, width, pillar spacing, etc.). Micro-pillars are fabricated on the hydrophilic silicon wafers by standard microfabrication processes, including metal etch mask patterning by photolithography, metal deposition, and lift-off to achieve the designed pillar shapes and spacing, and followed by dry etching for various pillar heights. Micrometer-sized drops of glycerol mixtures impacting micro-structured wafers are investigated using high-speed video photography. Impact velocities are varied to observe the influence of Weber number on the dynamic properties of the rebounding jet and jet initiation time, as well as whether or not the jet detaches ejecting satellite droplets normal to the substrate surface. The specific influence of the micro-patterned surfaces on maximum spreading, jet formation, jet tip velocity, and jet ejection is characterized. We find that the micro-patterned substrates have a significant effect on the behavior of the drop impact and jetting mechanism. From our experiments, we find that jet velocity is approximately 4 times that of the drop impact velocity. The jet formation time is shown to follow the capillary time scale as (ρDi3/σ)½ (where ρ, Di, and σ are density, initial droplet diameter, and surface tension, respectively).

Surface Functionalization of Biomaterials with Alkaline Phosphatase

2007 ◽  
Vol 361-363 ◽  
pp. 593-596 ◽  
Author(s):  
Enrica Verné ◽  
Sara Ferraris ◽  
Chiara Vitale-Brovarone ◽  
Silvia Spriano ◽  
Claudia Letizia Bianchi ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Titanium Alloy ◽  
Surface Functionalization ◽  
Glass Ceramics ◽  
The Other ◽  
Metallic Surfaces ◽  
Hard Tissues ◽  
Mineralization Processes ◽  
Titanium Alloy Ti6al4v

Two different glasses, one biocompatible but with a low bioactivity index (G1) and the other with an higher bioactivity index (G2), the ceramic version of the second glass and a titanium alloy (Ti6Al4V) have been functionalizated by anchoring alkaline phosphatase (ALP) on their surfaces. The enzyme has been chosen because it is involved in mineralization processes of hard tissues and is a model for more complex ones. ALP has been grafted on glasses and glass-ceramics surfaces both with and without samples silanization and on metallic surfaces with and without tresyl chloride activation. Samples have been analyzed at each step of the functionalization process in order to verify it.

scholarly journals Influence of the beam oscillation parameters on the porosity of electron beam freeform fabricated titanium alloy SPT-2

2021 ◽  
Vol 2077 (1) ◽  
pp. 012005
Author(s):  
A V Gudenko ◽  
A P Sliva ◽  
D V Shishkin
Keyword(s):  
Titanium Alloy ◽  
Electron Beam ◽  
Focal Plane ◽  
Pore Formation ◽  
Substrate Surface ◽  
X Ray ◽  
Freeform Fabrication ◽  
Technological Tool ◽  
Concentric Circles ◽  
Beam Oscillation

Abstract The effect of electron beam oscillation on the formation of metal during electron beam freeform fabrication has received practically no attention. Nevertheless, it is a variable technological tool that allows to significantly influence the formation of metal during EBFFF process, including the probability of defects formation. The effect of the focus current, the form, and the frequency of the beam oscillation on the formation of pores in single beads by method of electron beam freeform fabrication of the titanium alloy SPT-2 on the substrate of the alloy VT6 was investigated. The porosity of the obtained beads was studied using x-ray images. It was found that too deep an arrangement of the focal plane relative to the substrate surface leads to excessive pore formation. Reducing the oscillation frequency from 1000 Hz to 100 Hz made it possible to completely get rid of the pores in the metal. The use of a spiral-shaped oscillation made it possible to reduce the probability of pore formation in comparison with an oscillation in the form of concentric circles.

Electron microscopy studies of plasma-sprayed materials

1983 ◽  
Vol 41 ◽  
pp. 70-71
Author(s):  
K.R. Subramanian ◽  
A.H. King ◽  
H. Herman
Keyword(s):  
Plasma Spraying ◽  
Substrate Surface ◽  
Flame Temperature ◽  
Ceramic Coatings ◽  
Metallic Substrates ◽  
Hot Plasma ◽  
Almost All ◽  
Plasma Sprayed ◽  
Hostile Environments ◽  
Plasma Spraying Process

Plasma spraying is a technique which is used to apply coatings to metallic substrates for a variety of purposes, including hardfacing, corrosion resistance and thermal barrier applications. Almost all of the applications of this somewhat esoteric fabrication technique involve materials in hostile environments and the integrity of the coatings is of paramount importance: the effects of process variables on such properties as adhesive strength, cohesive strength and hardness of the substrate/coating system, however, are poorly understood.Briefly, the plasma spraying process involves forming a hot plasma jet with a maximum flame temperature of approximately 20,000K and a gas velocity of about 40m/s. Into this jet the coating material is injected, in powder form, so it is heated and projected at the substrate surface. Relatively thick metallic or ceramic coatings may be speedily built up using this technique.

XRF and PIXE Analysis of light and Dark Adapted Ocular Tissue

1982 ◽  
Vol 40 ◽  
pp. 190-191
Author(s):  
B. J. Panessa ◽  
H. W. Kraner ◽  
J. B. Warren ◽  
K. W. Jones
Keyword(s):  
Trace Metals ◽  
Pigment Epithelium ◽  
Nerve Impulse ◽  
Light Response ◽  
Ocular Tissue ◽  
Emission Spectrometry ◽  
Retinol Dehydrogenase ◽  
Pixe Analysis ◽  
X Ray ◽  
Optimal Function

During photoexcitation the retina requires specific electrolytes and trace metals for optimal function (Na, Mg, Cl, K, Ca, S, P, Cu and Zn). According to Hagins (1981), photoexcitation and generation of a nerve impulse involves the movement of Ca from the rhodopsin-ladened membranes of the rod outer segment (ROS) to the plasmalemma, which in turn decreases the in-flow of Na into the photoreceptor, resulting in hyperpolarization. In toad isolated retinas, the presence of Ba has been found to increase the amplitude and prolong the delay of the light response (Brown and Flaming, 1978). Trace metals such as Cu, Zn and Se are essential for the activity of the metalloenzymes of the retina and retina pigment epithelium (RPE) (i.e. carbonic anhydrase, retinol dehydrogenase, tyrosinase, glutathione peroxidase, superoxide dismutase...). Therefore the content and fluctuations of these elements in the retina and choroid are of fundamental importance for the maintenance of vision. This paper presents elemental data from light and dark adapted frog ocular tissues examined by electron beam induced x-ray microanalysis, x-ray fluorescence spectrometry (XRF) and proton induced x-ray emission spectrometry (PIXE).

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