Generating micro/nanostructures on magnesium alloy surface using ultraprecision diamond surface texturing process

The lightness and high strength-to-weight ratio of the magnesium alloy have attracted more interest in various applications.However,micro/nanostructure generation on their surfaces remains a challenge due to the flammability and ignition.Motivated by this,this study proposed a machining process,named the ultraprecision diamond surface texturing process,to machine the micro/nanostructures on magnesium alloy surfaces.Experimental results showed the various microstructures and sawtooth-shaped nanostructures were successfully generated on the AZ31B magnesium alloy surfaces,demonstrating the effectiveness of this proposed machining process.Furthermore,sawtooth-shaped nanostructures had the function of inducing the optical effect and generating different colors on workpiece surfaces.The colorful letter and colorful flower image were clearly viewed on magnesium alloy surfaces.The corresponding cutting force,chip morphology,and tool wear were systematically investigated to understand the machining mechanism of micro/nanostructures on magnesium alloy surfaces.The proposed machining process can further improve the performances of the magnesium alloy and extend its functions to other fields,such as optics.

Texturing and evaluation of concrete pavement surface:A state-of-the-art review

Concrete pavement is accompanied by two major functional properties,namely noise emission and friction,which are closely related to pavement surface texture.While several technologies have been developed to mitigate tirepavement noise and improve driving friction by surface texturization,limited information is available to compare the advantages and disadvantages of different surface textures.In this study,a state-of-the-art and state-of-thepractice review is conducted to investigate the noise reduction and friction improvement technologies for concrete pavement surfaces.The commonly used tests for characterizing the surface texture,skid resistance,and noise emission of concrete pavement were first summarized.Then,the texturing methods for both fresh and hardened concrete pavement surfaces were discussed,and the friction,noise emission and durability performances of various surface textures were compared.It is found that the next generation concrete surface(NGCS)texture generally provides the best noise emission performance and excellent friction properties.The exposed aggregate concrete(EAC)and optimized diamond grinding textures are also promising alternatives.Lastly,the technical parameters for the application of both diamond grinding and diamond grinding&grooving textures were recommended based on the authors'research and practical experience in Germany and the US.This study offers a convenient reference to the pavement researchers and engineers who seek to quickly understand relevant knowledge and choose the most appropriate surface textures for concrete pavements.

Analysis of Machinable Structures and Their Wettability of Rotary Ultrasonic Texturing Method

Tailored surface textures at the micro- or nanoscale dimensions are widely used to get required functional performances.Rotary ultrasonic texturing(RUT) technique has been proved to be capable of fabricating periodic micro- and nanostructures. In the present study, diamond tools with geometrically defined cutting edges were designed for fabricating different types of tailored surface textures using the RUT method. Surface generation mechanisms and machinable structures of the RUT process are analyzed and simulated with a 3D-CAD program. Textured surfaces generated by using a triangular pyramid cutting tip are constructed. Different textural patterns from several micrometers to several tens of micrometers with few burrs were successfully fabricated, which proved that tools with a proper two-rake-face design are capable of removing cutting chips efficiently along a sinusoidal cutting locus in the RUT process. Technical applications of the textured surfaces are also discussed. Wetting properties of textured aluminum surfaces were evaluated by combining the test of surface roughness features. The results show that the real surface area of the textured aluminum surfaces almost doubled by comparing with that of a flat surface, and anisotropic wetting properties were obtained due to the obvious directional textural features.

Picosecond Laser Surface Texturing of a Stavax Steel Substrate for Wettability Control

In this investigation,a picosecond laser was employed to fabricate surface textures on a Stavax steel substrate,which is a key material for mold fabrication in the manufacturing of various polymer products.Three main types of surface textures were fabricated on a Stavax steel substrate:periodic ripples,a two-scale hierarchical two-dimensional array of micro-bumps,and a micro-pits array with nanoripples.The wettability of the laser-textured Stavax steel surface was converted from its original hydrophilicity into hydrophobicity and even super-hydrophobicity after exposure to air.The results clearly show that this super-hydrophobicity is mainly due to the surface textures.The ultrafast laserinduced catalytic effect may play a secondary role in modifying the surface chemistry so as to lower the surface energy.The laser-induced surface textures on the metal mold substrates were then replicated onto polypropylene substrates via the polymer injection molding process.The surface wettability of the molded polypropylene was found to be changed from the original hydrophilicity to superhydrophobicity.This developed process holds the potential to improve the performance of fabricated plastic products in terms of wettability control and easy cleaning.

Surface texturing for adaptive Ag/MoS_2 solid lubricant plating

The objective of this research is to prepare specially designed surface texture on hard steel surface by electrochemical micromachining (EM) and to incorporate electroless plated Ag/MoS2 solid lubricant coating into the dimples of EM textured steel surface to effectively reduce friction and wear of steel-steel contacts. The friction and wear behavior of the Ag/MoS2 solid lubricant coating on EM textured steel surface was evaluated in relation to the size and spacing of the dimples thereon. The microstructure of as-plated Ag/MoS2 solid lubricant coating and the morphology and elemental composition of the worn coating surface and counterface steel surface were analyzed by means of optical microscopy, scanning electron microscopy, and energy dispersive spectrometry. It is found that electroless plated Ag/MoS2 coating is able to greatly reduce the friction and wear of the EM textured steel disc coupled with GCr15 steel ring, mainly because of the formation of solid self-lubricating layer on the EM textured steel surface and of transferred lubricating film on counterface steel surface. The diameter and spacing of the dimples are suggested as 500 μm for acquiring the best wear resistance of the hard steel discs after electrochemical micromachining treatment and electroless plating of Ag/MoS2 solid lubricating coating.

Fabrication of ceramic coatings on the biodegradable ZM21 magnesium alloy by PEO coupled EPD followed by laser texturing process

Zirconia(ZrO_2)incorporated ceramic coatings were fabricated on biodegradable ZM21 Mg alloy by the PEO coupled with EPD process.Subsequently,the sample surface was modified by laser texturing to improve the corrosion resistance,roughness and cell proliferation and growth properties.The corrosion performance of the fabricated samples along with the substrate was studied by electrochemical measurements under simulated body fluid(SBF)environment.The cell direct contact assay was conducted for the substrate and fabricated samples using L-929 mouse fibroblast cells for 24 h.The phase contrast images of cell direct contact assay revealed that fabricated samples exhibited better contact and response with the fibroblast cells,compared to the substrate.The addition of nanoparticles in the PEO process,called PEO coupled EPD process,resulted in attaining a higher thickness and improved corrosion performance of the samples than the PEO coated samples.Among all the samples,laser surface textured PEO,and PEO-EPD coated samples unveiled enhanced corrosion resistance,cell growth,thereby enabling it as a suitable prototype for biodegradable implant applications.

Surface Texturing of TiO_2 Film by Mist Deposition of TiO_2 Nanoparticles

Unique and various microstructures of titanium oxide(TiO_2 ) film including macroporous structure, chromatic veins and rings, have been easily fabricated by mist deposition method on silicon substrate with mild preparation conditions. Rutile phase TiO_2 nanoparticles were directly used as starting material to prepare film and led to a simple preparation process. It was found that several different microstructures existed in the sample and changed with the varied positions from the center to the edge of the film when the concentration of the TiO_2 suspension is 0.06 mol/l, the deposition time is 30 min, the flow rate is 1 l/min and the temperature is150. The surface texturing shows apparent distinction as the concentration of the TiO_2 suspension decreased to 0.03 mol/l and 0.01 mol/l.

Effect of Surface Texturing on Lubricating Condition under Point Contact Using Numerical Analysis

The contact fatigue life of machine elements is affected by pitting, wear and so on, under heavier loading conditions. Increasing the fatigue life requires mainly the improvements of lubricating condition, operating condition and materials. In order to improve the lubricating condition, it is necessary to investigate the relation of the microscopic surface texturing and the contact modes of machine elements. In this paper, thus, the pressure and oil film thickness of the contact between sphere and the plate with 5 kinds surface texturing were calculated using a commercial software based on Reynolds equation. There was sufficient evidence to suggest that the dimple shape was the optimum texturing to increase the lubricating condition.

RELATION BETWEEN STRUCTURE OF PP DRAWN FILAMENT AND TEXTURING EFFECT

The relationship between the structure of PP drawn filament and the crimp elasticity of tex-tured yarn is investigated.It is found that orientation,crystallinity,and especially,crystalline formof drawn filament are related to crimp property of textured yarn.Lower crystallinity,moderateorientation and unstable para-crystalline structure are necessary for increasing crimp elasticity.Inaddition,the filament structure and properties before and after texturing are compared.

Air-flow Analysis for BCF Texturing Tube

In this paper,the Reynolds number,velocity,pressureand kinetic energy of the BCF processing hot air-floware analyzed with the help of the aero-dynamic theory,and their distributions inside the texturing tube are ob-tained by pressure measuring.

A unified computational model for surface texturing process of strip casting rollers

A new unified computational method is proposed for modeling the relationship between the parameters of the high-speed particle-impact texturing process and the final surface morphology of the casting roller. The whole surface-texturing process is divided into three parts. The first part is the acceleration process of particles inside and outside the nozzle,which can be analyzed using the computational fluid dynamics method to obtain the particle impact velocities. The second part is a simulation of the bombardment process of particles onto the roller surface using the LS-DYNA software as the analysis tool and the results obtained in the first part as input parameters. The last part is the continuously random impact process of particles on the casting roller surface to form a functional surface,which is characterized by a simplified roughness model. Finally,the above three parts are combined to establish a unified computational model,the performance of which is successfully verified in a series of experiments.

Effect of Laser Texturing Parameters on Wettability of Nickel Surface

Wettability is an important characteristic of solid surfaces. Enhancing the surface wettability is very important for improving the properties of materials. Superhydrophobic materials show good prospects for development in areas such as self-cleaning, anti-fog snow, anti-icing, and corrosion resistance. It has become a hot spot to develop a superhydrophobic surface with low surface free energy and good anti-adhesion properties. In this paper, nanosecond pulsed lasers were used to texture the nickel surface, and the different texturing speeds were changed. Combined with the ultrasonic treatment of low surface energy materials, nickel surfaces with different contact angles were obtained. The experimental results show that low surface energy substances can increase the contact angle of nickel surface but the extent of increase is limited. Laser microstructure induces micro & nanostructures. Ultrasonic action can adsorb certain low surface energy substances on the surface, greatly improving the hydrophobic properties of the surface, the contact angle with water up to 152? and the roll angle is less than 2?, and with the increase of the laser texturing speed, the contact angle of the nickel surface shows a decreasing trend.

Controlled Texturing of Aluminum Sheet for Solar Energy Applications

Aluminum sheets were polished to reduce ruggedness and then textured in varying acid-ethanol concentration etchant to form pores. The textured surface was characterized structurally by using X-ray diffraction (XRD) which revealed aluminum crystallographic planes (1 1 1), (2 0 0), (2 2 0) and (3 1 1). Its morphology was studied by using energy dispersive X-ray (EDX) and scanning electron microscope (SEM) that confirmed purity of aluminum sheet to be 99.66% at. Reflectance of textured and plain aluminum sheet was analyzed by spectrophotometric measurements which showed that texturing reduced the reflectance of the polished surface by 26% in the UV-VIS-NIR spectrum of solar radiation. With reduced reflectance of the textured aluminum sheet, it was applicable for solar radiation absorption.

Continuous Wave Diode Laser Surface Texturing of Austenitic and Pearlitic Steels

Microstructuring of steel resulting in directional solidification and texturing, previously observed in various metallic materials during pulsed laser processing, melt-spinning, high-gradient liquid metal melting, zone melting etc., is reported for the first time in continuous wave diode laser processing of steels. Influence of laser interaction time on surface morphology/topology of austenitic manganese and pearlitic steels is investigated utilizing a wide rectangular multi-mode diode laser beam. X-ray diffraction analysis of the laser treated austenitic steel surface showed strong texturing influence, with preferred crystallographic orientation of γ-Fe crystals in the (200) plane, which increased with interaction time. In case of pearlitic steel, no such texturing influence could be observed. The free surface topologies were also observed to be different in each case, with well-aligned domes of γ-Fe observed in laser treated austenitic steel as compared to randomly oriented fine domes of metal oxides in pearlitic one. In situ surface temperature measurement during laser irradiation indicated higher temperature on pearlitic steel than in austenitic manganese steel owing to its lower effective thermal conductivity associated with higher oxide film formation.

TEXTURING TOOLKIT贴图工具包

为2D插画或者3D模型创建帖图和材质是件需要花费大量时间的工作。你需要耗费大量的时间带着你的照相机去搜寻完美的帖图图片．而将帖图映射到3D模型上则需要相当专业的技术实现起来并不容易。

STUDY OF PET AIR-JET TEXTURING SEWING THREAD PROPERTIES

This paper presents a study of properties of air-jet textured threads made from high strengthpolyester filament and ordinary strength polyester filament.It includes the evaluation of tenacity,breaking elongation,modulus,specific work,evenness,abrasion resistance,hook strength,knotstrength and other mechanical properties relating to sewing.The polyester air-jet texturing sewingthread has special structure and appearance and possesses better properties of evenness,goodabrasion resistance,fatigue property,high hook and knot strength.

Real Time Collision Detection Using Depth Texturing Spheres

In this paper,we present a novel collision detection algorithm to real time detect the collisions of objects.We gen- erate sphere textures of objects,and use programmable graphics hardware to mapping texture and check the depth of different ob- jects to detect the collision.We have implemented the algorithm and compared it with CULLIDE.The result shows that our algo- rithm is more effective than CULLIDE and has fixed executive time to suit for real-time applications.

Rapid surface texturing to achieve robust superhydrophobicity,controllable droplet impact,and anti-frosting performances

Robust superhydrophobic surfaces with excellent capacities of repelling water and anti-frosting are of importance for many mechanical components.In this work,wear-resistant superhydrophobic surfaces were fabricated by curing a mixture of polyurethane acrylate(PUA)coating and 1H,1H,2H,2H-Perfluorodecyltrichlorosilane(HFTCS)on titanium alloy(TC4)surfaces decorated with micropillars pattern,thus,composite functional surfaces with PUA coating in the valleys around the micropillars pattern of TC4 were achieved.Apparent contact angle on fabricated surfaces could reach 167°.Influences of the geometric parameters of micropillars pattern on the apparent contact angle were investigated,and the corresponding wear-resistant property was compared.Droplet impact and anti-frosting performances on the prepared surfaces were highlighted.An optimized design of surface texture with robust superhydrophobicity,controllable droplet impact,and anti-frosting performances was proposed.This design principle is of promising prospects for fabricating superhydrophobic surfaces in traditional mechanical systems.

Laser Surface Texturing of Co–Cr–Mo Alloy for Biomedical Applications:A Case Study for the Effects of Process Parameters on Surface Properties

This study presents a comprehensive approach to applying texturing processes created by engraving on the surface of CoCr28Mo alloy workpieces using a 20 W pulsed nanosecond fiber laser.The hatch strategy and distance,frequency,and scan speed were control parameters for texturing applications.The effectiveness of the parameters in terms of roughness and contact angle of the texturized surface was investigated.Surface roughness and contact angle were analyzed using variance analysis to identify each variable's influence.It has been determined that the roughness of the texture defined by the hatch strategy plays a decisive role in the wettability behavior of the surface;however,the scan speed,frequency,and hatch distance which are among the laser surface texturing conditions are influential in the roughness and contact angle.Increasing scan speed and hatch distance while decreasing frequency resulted in smoother surfaces,increasing the contact angle.Textures having rough surfaces produced with different processing conditions exhibit a super hydrophilic behavior.The contact angle is most sensitive to the hatch distance;however,the frequency has the least influence on the contact angle.The most and least efficient surface roughness parameters are revealed to be scan speed and hatch distance,respectively.

Tribological properties of hierarchical micro-dimples produced on a cylindrical surface by dual-frequency texturing

An experimental investigation was performed for investigating the tribological performance of micro-dimple surface texture patterns on a cylindrical surface in a realistic operating environment of starved lubrication. Micro-dimples were generated by a dual-frequency surface texturing method, in which a high-frequency (16.3 kHz) three-dimensional (3D) vibration and a low-frequency (230 Hz) one-dimensional (1D) vibration were applied at the tool tip simultaneously, resulting in the generation of the hierarchical micro-dimples in a single step. Rotating cylinder-on-pin tribological tests were conducted to compare the tribological performance of the non-textured reference specimen and micro-dimple samples. The effect of surface textures generated with various shape parameters (long drop and short drop), dimension parameters (length and surface texture density), and operation parameters (load and sliding velocity) on the tribological performance was evaluated. Stribeck curves indicate that the hierarchical micro-dimples exhibit a lower coefficient of friction than the reference specimen in the high contact-pressure regions. It is also observed that variation in the length of a micro-dimple, the shape effect, is the major factor affecting the friction response of the textured surfaces. The generation of additional hydrodynamic pressure and lift effect by hierarchical structures is the main reason for the improved performance of hierarchical micro-dimple surfaces.