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In this study, the friction surfaced Al–Si–Cu alloy coating was processed using a low rotational speed, fast multiple rotation rolling (FMRR) process. The effect of traverse speed in the range of 50–200 mm/min at a rotational speed of 600 rpm on the microstructure, mechanical properties, and wear resistance of the Al–Si–Cu alloy coating was investigated. The results showed that compared to the initial friction surfaced coating, the thickness of the coating decreased by 44% and the width of the coating increased by 21% with a decrease in traverse speed from 200 to 50 mm/min. By increasing the traverse speed from 50 to 200 mm/min, the thickness of the processed layer decreased from 102.3 ± 1.1 µm to 54.2 ± 1.3 µm, and the grain size of the processed layer decreased from 2.4 ± 0.1 µm to 1.1 ± 0.2 µm. As the traverse speed increased from 50 to 200 mm/min, the average hardness of the FMRR processed layer increased from 6.7 ± 0.4 GPa to 9.7 ± 0.4 GPa. Additionally, at a traverse speed of 200 mm/min and a rotational speed of 600 rpm, the wear resistance of the FMRR processed layer increased by 65% compared to the AA1050 aluminum substrate. [ABSTRACT FROM AUTHOR]

Abstract—The features of the method for generating gas-vapor plasma and the characteristics of a high-power ion beam (HPIB) obtained in a vacuum diode with a graphite cathode using a plasma-forming high-voltage nanosecond pulse are described. The cathode material and the two-pulse mode of operation of the TEMP-4 type diode make it possible to form a multicomponent nanosecond HPIB with a maximum ion energy of up to 1 MeV, a particle flux density on the surface of ~1013 ion/cm2, and a power density on the sample surface of up to 107 W/cm2 to modify the surface properties of structural materials. Materials are published within the framework of scientific discussion. The authors invite researchers of the generation of high-power beams of non-gas ions and the processes of beam modification of solid-state materials to discuss the topics of this article. [ABSTRACT FROM AUTHOR]

The review summarizes the progress achieved in the surface modification of NiTi shape memory alloys (SMAs) with laser and electron beams in terms of their compliance with the requirements for biomedical devices and implants. The main provisions of the standards regulating this area of activity are aggregated. The production routes for manufacturing bulk items from NiTi SMAs are described. Since the formation of surface alloys on NiTi SMAs is now an intensively growing area of research, the influence of additional alloying elements on their functional properties is also discussed. The common patterns of interaction of laser and electron radiation with NiTi SMAs are specified. The typical requirements for surface layer conditions and conventional methods for their modification are reported. The results of various laser processing methods, differing in energy parameters, atmospheres and beam scanning algorithms, are summarized. They include remelting, annealing, nitriding, shock peening, alloying and texturing. In addition, some data on the modification and alloying of the surface layers with high-current pulsed electron beams are integrated. Finally, the aggregated information is compared and analyzed from the point of view of its prospects in these research areas. [ABSTRACT FROM AUTHOR]

The basic mechanisms of laser interaction with synthetic diamond are reviewed. The characteristics of the main regimes of diamond surface etching are considered. In addition to the well-known graphitization and ablation processes, nanoablation and accumulative graphitization, which have attracted relatively recent attention, are described in detail. The focus is on femtosecond (fs) laser exposure, which allows for the formation of a dense cold electron–hole plasma in the focal zone and minimal overheating in the surrounding area. This potentially opens the way to the development of unique laser-based technologies that combine physical and chemical processes for precise surface treatment and functionalization. The physical limitations that determine how precisely the diamond surface can be treated by short-pulsed laser radiation and possible ways to overcome them with the ultimate goal of removing ultrathin layers of the material are discussed. Special attention is paid to the novel possibility of inducing the local formation of point active defects—nitrogen vacancy (NV) complexes in the laser-irradiated zone. Such defects have been at the forefront of solid-state physics for the past thirty years due to continuous attempts to exploit their unique properties in quantum optics, quantum computing, magnetometry, probing, and other fields. Both regimes of NV center formation with and without graphitization of the diamond lattice are considered. Thus, it is shown that intense pulsed laser irradiation is a perfect tool for the processing of synthetic diamonds at the micro-, nano-, and even at the atomic level, which can be well controlled and managed. [ABSTRACT FROM AUTHOR]

Surface Plasmonic Resonance (SPR) induced by metallic nanoparticles can be exploited to enhance the response of photodetectors (PD) to a large degree. Since the interface between metallic nanoparticles and semiconductors plays an important role in SPR, the magnitude of the enhancement is highly dependent on the morphology and roughness of the surface where the nanoparticles are distributed. In this work, we used mechanical polishing to produce different surface roughnesses for the ZnO film. Then, we exploited sputtering to fabricate Al nanoparticles on the ZnO film. The size and spacing of the Al nanoparticles were adjusted by sputtering power and time. Finally, we made a comparison among the PD with surface processing only, the Al-nanoparticles-enhanced PD, and the Al-nanoparticles-enhanced PD with surface processing. The results showed that increasing the surface roughness could enhance the photo response due to the augmentation of light scattering. More interestingly, the SPR induced by the Al nanoparticles could be strengthened by increasing the roughness. The responsivity could be enlarged by three orders of magnitude after we introduced surface roughness to boost the SPR. This work revealed the mechanism behind how surface roughness influences SPR enhancement. This provides new means for improving the photo responses of SPR-enhanced photodetectors. [ABSTRACT FROM AUTHOR]

This work is devoted to classical molecular dynamics simulations of surface modifications (craters) drilled by single femtosecond laser pulses in silicon and diamond, materials relevant for numerous industrial applications. We propose a methodology paving the way towards a significant decrease in the simulation computational costs, which could also enable a precise estimation of the craters’ size and shape.

Getting students to engage in reflective thought is a «wicked» problem in teaching. Students may demonstrate a resistance to any form of reflection, analysis or critical thought and instead automatically default to surface approaches which are non-productive in academic contexts. This resistance may involve an aversion which leads to students not persisting to higher levels of education and dropping out. The present study investigates the relationship between the resistance to reflective processing and persistence in education using the Cognitive Reflection Test (CRT) and some additional survey items aimed at testing surface processing tendencies in non-academic contexts. It provides support for the hypothesis that a general aversion to reflective processing appears to inhibit academic progression and correlates with drop-out from courses midstream. It closes by suggesting that aversion to analytical thinking may be a threshold issue that needs to be addressed separately before students can progress to any challenging content.

A universal method to fabricate LM membrane on multiple polymeric substrates based on interlocking interface has been proposed, which improves interfacial compatibility and introduces strong binding between LM and the polymer substrate. The LM membrane could be used to construct soft phothothermal actuators. [Display omitted] The high surface tension of liquid metal (LM) causes interface incompatibility and poor bonding strength with many substrates. Fine adjustment towards the properties of the surface area is sufficient to introduce strong bonding. Hence, we hypothesize that the interlocking structure using hydrophilic polyvinyl alcohol (PVA) as a "bridge" should be helpful for tight interfacial bonding of LM with polymeric substrates, thus achieving high-performance LM/polymer membranes, which have wide applications in the field of soft sensors and robotics. The bulk EGaIn was fabricated into LM nanoparticles (LMNPs@PVA) solution. Then, PVA molecules were "doped" into the surface crosslink of the plasma treated polymer substrate by an interfacial penetrating method. Afterward, the solution was evenly dropped on the surface of the treated substrate to obtain the LMNP/polymer membrane after the water evaporated. Photothermal actuators were fabricated based on the membranes. During the interlocking structure, PVA macromolecules could be doped and trapped onto the top surfaces of various polymer substrates as binding "bridges" between the LMNPs and the matrix materials. The achieved LMNP membrane exhibites satisfactory bonding strength, durability and water-assisted erase-reprint, which can be used as soft photothermal actuators with remote laser control. [ABSTRACT FROM AUTHOR]

The physical properties of silicon carbide (SiC) are excellent as a third-generation semiconductor. Nevertheless, diamond wire cutting has many drawbacks, including high loss, long cutting time and prolonged processing time. The study of 4H-SiC wafer slicing by using an ultrafast laser is hopeful for solving these problems. In this work, the 4H-SiC samples with different surface roughness were processed by laser slicing. Findings revealed that good surface quality could reduce the damage to the wafer surface during laser slicing, reduce cleavage, and improve the flatness and uniformity of the modified layer. Thus, preprocessing on 4H-SiC can significantly improve the quality and efficiency of laser slicing. [ABSTRACT FROM AUTHOR]

We introduce spectral-based convolutional operators embedded within Generalized Graph Neural Networks (G-GNNs). These operators enable deep learning on graphs through a learnable, energy-driven evolution process. This approach empowers us to impose specific properties on the graph convolutional kernel directly derived from the corresponding variational formulations. Our model incorporates both parameterized and non-parameterized graph Laplacian-based energies within the generalized graph convolutional layer to address features like smoothness, sharpness, and compact support. By making appropriate choices within our G-GNN framework, we pave the way for designing novel paradigms for 3D shape representation, reconstruction, and processing, while also enabling effective feature embeddings for intrinsic neural fields. [ABSTRACT FROM AUTHOR]

The basic mechanisms of laser interaction with synthetic diamond are reviewed. The characteristics of the main regimes of diamond surface etching are considered. In addition to the well-known graphitization and ablation processes, nanoablation and accumulative graphitization, which have attracted relatively recent attention, are described in detail. The focus is on femtosecond (fs) laser exposure, which allows for the formation of a dense cold electron–hole plasma in the focal zone and minimal overheating in the surrounding area. This potentially opens the way to the development of unique laser-based technologies that combine physical and chemical processes for precise surface treatment and functionalization. The physical limitations that determine how precisely the diamond surface can be treated by short-pulsed laser radiation and possible ways to overcome them with the ultimate goal of removing ultrathin layers of the material are discussed. Special attention is paid to the novel possibility of inducing the local formation of point active defects—nitrogen vacancy (NV) complexes in the laser-irradiated zone. Such defects have been at the forefront of solid-state physics for the past thirty years due to continuous attempts to exploit their unique properties in quantum optics, quantum computing, magnetometry, probing, and other fields. Both regimes of NV center formation with and without graphitization of the diamond lattice are considered. Thus, it is shown that intense pulsed laser irradiation is a perfect tool for the processing of synthetic diamonds at the micro-, nano-, and even at the atomic level, which can be well controlled and managed.

In this work, friction stir processing using a pinless tool with a featured shoulder was performed to alter the surface properties of Al 6061-O, focusing on the effect of tool traverse speed on surface properties, i.e., microstructure, hardness, and corrosion resistance. All processed samples showed refinement in grain size, microhardness, and corrosion resistance compared to the base material. Increasing tool-traverse speed marginally refined the microstructure, but produced a significant reduction in microhardness. Electrochemical impedance spectroscopy, linear polarization resistance, and potentiodynamic polarization were used to evaluate the effect of the processing conditions on corrosion behavior in a saline environment. All corrosion test results are found to agree and were supported with pictures of corroded samples captured using a field emission scanning electron microscope. A remarkable reduction in the corrosion rate was obtained with increasing traverse speed. At the highest traverse speed, the corrosion current density dropped by approximately 600 times when compared with that of the base alloy according to potentiodynamic polarization results. This is mainly due to the grain refinement produced by the friction stir process. [ABSTRACT FROM AUTHOR]

This work is devoted to classical molecular dynamics simulations of surface modifications (craters) drilled by single femtosecond laser pulses in silicon and diamond, materials relevant for numerous industrial applications. We propose a methodology paving the way towards a significant decrease in the simulation computational costs, which could also enable a precise estimation of the craters' size and shape. [ABSTRACT FROM AUTHOR]

Surface Plasmonic Resonance (SPR) induced by metallic nanoparticles can be exploited to enhance the response of photodetectors (PD) to a large degree. Since the interface between metallic nanoparticles and semiconductors plays an important role in SPR, the magnitude of the enhancement is highly dependent on the morphology and roughness of the surface where the nanoparticles are distributed. In this work, we used mechanical polishing to produce different surface roughnesses for the ZnO film. Then, we exploited sputtering to fabricate Al nanoparticles on the ZnO film. The size and spacing of the Al nanoparticles were adjusted by sputtering power and time. Finally, we made a comparison among the PD with surface processing only, the Al-nanoparticles-enhanced PD, and the Al-nanoparticles-enhanced PD with surface processing. The results showed that increasing the surface roughness could enhance the photo response due to the augmentation of light scattering. More interestingly, the SPR induced by the Al nanoparticles could be strengthened by increasing the roughness. The responsivity could be enlarged by three orders of magnitude after we introduced surface roughness to boost the SPR. This work revealed the mechanism behind how surface roughness influences SPR enhancement. This provides new means for improving the photo responses of SPR-enhanced photodetectors.

Plasma electrolytic polishing (PEP) has been gaining increased attention as a replacement for electrochemical polishing (EP) processes. It significantly enhances metal surface properties in terms of surface roughness and corrosion resistance. In contrast to EP, PEP does not require any preliminary workpiece cleaning or treatment with hazardous acids. However, PEP in bath applications yields inhomogeneous polishing results and, in particular, cannot polish more complex geometries such as cavities. To overcome these issues and to enhance the control of local polishing effects on metal workpieces, the use of a PEP jet is investigated. A jet configuration enables higher PEP control and increases PEP polishing rates by a factor of six compared to a polishing bath as a result of higher localized current. [ABSTRACT FROM AUTHOR]

Enhancing the functionality of surfaces has increasingly become the focus of modern engineering in recent years. Functional material surfaces can be developed through targeted micro structuring. For example, surface modifications by micro structuring can change the wetting behaviour or effectively optimize the frictional properties. Some of these applications are already established on the market and e.g. used in case of improving highly stressed surfaces. To accelerate further research in this direction, the present work deals with the functionalization of surfaces with the aim of modifying optical properties. The overall vision for this is the production of functional enhanced additive manufactured free-form mirrors for technical applications. Nowadays, the additive manufactured metal mirrors need a complicated and time-consuming mechanical post-processing like e.g. manual polishing. To add a further functionalization, structures like e.g. optical gratings need a separate production step, mostly limited to one fix structure geometry and size. Thus, laser direct writing as an alternative method and highly flexible production process is examined. [ABSTRACT FROM AUTHOR]

To predict fatigue life more accurately, we consider the relationship between static toughness and fatigue toughness in fatigue failure process, the numerical model of total dissipated plastic strain energy (TDPSE) and fatigue life is established. And considering the effect of surface roughness and surface processing coefficient on fatigue life, the life prediction method of TDPSE is modified. In addition, the fatigue life of Non-Masing and Masing materials are predicted by TDPSE and modified TDPSE method, respectively. Compared with TDPSE method, the life estimated by the modified TDPSE method are closer to the test results, and the modified TDPSE method lays a technical foundation for the development of mechanical components. [ABSTRACT FROM AUTHOR]

The physical properties of silicon carbide (SiC) are excellent as a third-generation semiconductor. Nevertheless, diamond wire cutting has many drawbacks, including high loss, long cutting time and prolonged processing time. The study of 4H-SiC wafer slicing by using an ultrafast laser is hopeful for solving these problems. In this work, the 4H-SiC samples with different surface roughness were processed by laser slicing. Findings revealed that good surface quality could reduce the damage to the wafer surface during laser slicing, reduce cleavage, and improve the flatness and uniformity of the modified layer. Thus, preprocessing on 4H-SiC can significantly improve the quality and efficiency of laser slicing.

In this work, surface mechanical rolling treatment (SMRT) was applied as a post-process nanostructuring technique to improve the tribo-corrosion degradation resistance of coarse grain (CG) 316L stainless steel (SS). The experimental findings reveal that when tribo-corrosion wear took place, the CG specimen experienced severe surface de-passivation, which increased wear-corrosion synergy and the rate of material loss. On the other hand, the SMRT specimen experienced enhanced re-passivation kinetics, which reduced wear-corrosion synergy and the rate of material loss. The wear mechanism for both the CG and SMRT specimens was abrasion-dominant, with the CG specimen having the presence of micro-pits within the wear track. In addition to these findings, the reduced surface roughness, improved hardness, formed compressive stresses, microstructural refinement, and martensite phase transformation induced by the SMRT process contributed to the enhanced tribo-corrosion resistance of the SMRT specimen. In total, SMRT was found to be a feasible technique to improve the tribo-corrosion resistance of CG 316L SS. • The tribocorrosion (TC) behavior of surface nanostructured (SN) steel was studied. • SNing reduced surface roughness/grain size and increased surface hardness. • SNing improved TC repassivation kinetics and decreased wear-corrosion synergy. • Abrasive wear was the predominant wear mechanism for the SN'd steel. • Collectively, SNing is a viable technique to improve the TC resistance of steel. [ABSTRACT FROM AUTHOR]

[Display omitted] • The principle of laser cavitation was comprehensively studied. • The effects of process parameters on impact performance of laser cavitation were analyzed. • Different models of laser induced cavitation were investigated. • The processing performance of different materials by laser induced cavitation were investigated. • The development and potential applications of laser cavitation technology were prospected. Cavitation refers to the phenomenon of generating bubbles in water or other liquids. The collapse of cavitation bubbles will have a strong impact on the surrounding materials. Therefore, people have developed the technology of using cavitation bubbles to conduct the surface processing of materials. Laser induced cavitation is one of the multiple methods to generate cavitation bubbles. Laser induced cavitation has the advantages of strong controllability, good spherical symmetry, no mechanical deformation and precise positioning, so it is widely used in many fields, such as medical, aerospace, etc. In surface processing, cavitation bubble induced by laser in water or other liquids impacts the sample surface and causes it to strengthen or deform. In this paper, the current research status of laser induced cavitation surface processing is reviewed. The principle of laser cavitation surface processing and the model proposed by predecessors are summarized. It is considered that laser cavitation surface processing affects the mechanical properties of sample through three procedures: plasma impact, cavitation bubble collapse impact and water-jet impact. The influences of machining parameters on the impact process and impact effect are discussed and analyzed, especially the dynamic change of cavitation bubbles and the mechanical properties of sample surface. The effects of laser cavitation surface processing on micro-structure, surface morphology, hardness and strength are described. At last, the development of laser cavitation technology is summarized and prospected. As a mean to improve the mechanical properties and change the morphology of components, laser cavitation surface processing has a great development potential and a good development prospect in many fields. [ABSTRACT FROM AUTHOR]

This paper proposes an automatic surface treatment method for CNC milled blades. The surface texture characteristics of the blade after milling were analyzed. The contact area between the contact wheel and the blade surface was analyzed theoretically, and then the contact wheel and the blade edge were analyzed. The contact area between the intake side and the exhaust side was theoretically analyzed, and one micro-element in the contact area was selected, and the simulation analysis under multiple sets of parameters was carried out. In the experimental aspect, this paper has assembled a set of relatively reliable experimental systems, and carried out an in-depth analysis of a certain area of the engine blade obtained from the experiment to verify the feasibility and reliability of the proposed method.

The design and development process of custom‐made medical devices is very complex and often requires the use of additive manufacturing to obtain a customer compliant product. One of the key stages, but also very time consuming in the development of bespoke medical products, is the data acquisition of the patients' specific anatomy. The current research paper presents a detailed process of upper body data acquisition using 3D scanning protocols, with the goal of designing a custom smart spinal orthosis using generative design and additive manufacturing technologies. The initial captured cloud points are subjected successively to a series of surface manipulation and mesh optimization operations to generate the final working 3D model of the upper body. Each stage of the 3D model is obtained using a specific software application, as follows: *.DICOM images are generated using a 3D scanner software; *STL files are obtained by transforming initial files using MeshMixer software; *.STEP files are optimized using Fusion 360. Shape validation is done by 3D printing of a real scale upper body anatomical prototype using material extrusion. Authors also proposed a generative design process for the development of a personalized vertebral body from the construction of the smart spinal orthosis. The generative study is initialized with the following data: connection type, stress scenarios, material type (metals – Ti, Al, Steel; composites – ABS, PET, HIPS), and manufacturing technology (additive, subtractive, injection molding). A set of 49 converged outcomes is generated after running the study and three are selected for further research. [ABSTRACT FROM AUTHOR]

Due to the continually increasing popularity of metal powder-based additive manufacturing as a production process in recent years, there has been growing research into improving the surface quality of the parts manufactured in this way. Laser polishing offers great potential as a finishing technique due to its flexibility and suitability for automation. However, the complexity of components that can be produced with additive manufacturing processes presents challenges in developing practical and flexible arrangements for implementing a laser polishing process. In this paper, we offer methods to manage height variations of parts using weakly focused beams, process components that are (roughly) cylindrical using rotational stages, and polishing of internal surfaces using simple optics. As an example application, we present finishing of additively manufactured cobalt chrome dental implants to a surface roughness of 0.45 µm in only 60 s using a low-cost fiber delivered diode array laser. [ABSTRACT FROM AUTHOR]

Laser Shock Peening (LSP) is a process where high energy nanosecond laser pulses are used to modify surface characteristics of treated materials. In this work, the LSP process is briefly explained and its effects on roughness, hardness and residual stresses of aluminium alloy 5083 are demonstrated. The LSP process is based on small plastic deformation caused by laser impacts on the surface which naturally increases roughness. It has been shown that the increase in roughness can be partially mitigated by strategic overlapping of individual laser pulses. The hardness of the peened surface has been increased by 19% and uniform compressive residual stresses up to 200 MPa have been created over a large area. The compressive stresses reached about 1.2 mm deep inside the samples. [ABSTRACT FROM AUTHOR]

Magnesium, iron and zinc-based alloys are potential metallic biodegradable alloys for bioimplant applications. The issues of hydrogen evolution along magnesium's surface and the release of bulky corroded products of iron alloys during its usage necessitated to look for an alternate alloy system for biodegradable implant applications. Zn-Mg alloy is one such alternate alloy that is widely explored by several researchers. The typical cast microstructure of Zn-Mg alloy contains pro-eutectic α-Zn and eutectic mixture of α-Zn and Mg 2 Zn 11. The cast alloy exhibits poor ductility as the intermetallic Mg 2 Zn 11 phase exists only in eutectic mixture. Therefore, the cast alloys were subsequently processed through hot rolling, hot extrusion and rarely through severe plastic deformation to enhance the mechanical properties. In the current study, probably for the first time, friction stir processing (FSP) has been used to refine the microstructure of Zn-Mg alloys with an intention to enhance the mechanical properties. Indeed, it was a challenge to friction stir process the Zn alloys through friction stir processing, as they have poor ductility (< 10 %) in as-cast condition. By choosing tool rotational speed that can impart significant heat input to the processed regime, this study demonstrated successful FSP of Zn and Zn-(0.5, 1.0 & 2.0) wt% Mg alloys. The pure-Zn and Zn-Mg alloys are FSPed using constant tool traverse speed of 20 mm/ min and variable rotational speeds of 560, 710 and 900 rpm. Hardness of as-cast Zn was 32 VHN whereas addition of 2 % Mg increased it to 105 VHN. Hardness of zinc increased to 39 VHN after FSP using 560 rpm; at the same time, further increase of rotational speed retained the hardness around 40 VHN. On the other hand, hardness of Zn-Mg alloys significantly improved after FSP. Interestingly, hardness of alloys increased with the rotational speed. Usually, increase of rotational speed increases heat input in to the processed regime thus assists the development of coarse microstructure results in hardness degradation. An opposite trend has been observed in the current study. The reasons for this notable observation are found to be refinement of microstructure and redistribution of Mg 2 Zn 11 phase throughout α-Zn matrix that happened during FSP. • Zn-Mg alloy, probably for the first time, processed using friction stir processing. • Effect of tool rotational speed on microstructure refinement is investigated. • Hardness is doubled after FSP due to severe structure refinement. • Mg 2 Zn 11 phase in eutectic mixture is uniformly distributed in the matrix after FSP. [ABSTRACT FROM AUTHOR]

Objective: We aim to improve operational robustness of liquid scanning probes. Two main failure modes to be addressed are an obstruction of the flow path of the processing liquid and a deviation from the desired gap distance between probe and sample. Methods: We introduce a multi-functional design element, a microfluidic bypass channel, which can be operated in dc and in ac mode, each preventing one of the two main failure modes. Results: In dc mode, the bypass channel is filled with liquid and exhibits resistive behavior, enabling the probe to passively react to an obstruction. In the case of an obstruction of the flow path, the processing liquid is passively diverted through the bypass to prevent its leakage and to limit the buildup of high pressure levels. In ac mode, the bypass is filled with gas and has capacitive characteristics, allowing the gap distance between the probe and the sample to be monitored by observing a phase shift in the motion of two gas–liquid interfaces. For a modulation of the input pressure at 4 Hz, significant changes of the phase shift were observed up to a gap distance of 25 μm. Conclusion: The presented passive design element counters both failure modes in a simple and highly compatible manner. Significance: Liquid scanning probes enabling targeted interfacing with biological surfaces are compatible with a wide range of workflows and bioanalytical applications. An improved operational robustness would facilitate rapid and widespread adoption of liquid scanning probes in research as well as in diagnostics. [ABSTRACT FROM AUTHOR]

Generation of laser induced surface structures has been reported as an effective way to functionalize the surface of a solid material. Structure size, symmetry and hierarchical length scale formation has a significant influence on the material's macroscopic properties. The feasibility to produce surface morphologies at different scales is on high demand since they can be employed to mimic bio inspired morphologies in order to enable a variety of unexplored surface functionalities such as bactericidal, anti-icing and anti-reflective surfaces. In the present paper, we report on a comprehensive study dealing with laser induced surface structures morphology control, in terms of symmetry and size, utilizing a high throughput industrial femtosecond source with pulse duration of 350 fs. Interestingly, structures at the micron scale can be effectively tuned via fluence manipulation meanwhile tuning structures at the submicron scale requires double pulse irradiation with polarization modification. For double pulse irradiation the effect of polarization, fluence and overlap was investigated for interpulse delays up to 4 ns. We find out that a large variety of surface structures can be achieved by this way. We believe that our work provides novel data on surface texturing and pushes forward the level of technological readiness of laser surface functionalization. [ABSTRACT FROM AUTHOR]

Heavily loaded structural elements operating in a corrosive environment are usually quickly destroyed. An example of such an element is a ship propeller operating in a seawater environment. This research presents a fatigue resistance test performed on elements operating in seawater. Different processing parameters applied on the samples in particular were compared with the specimens whose surface had been burnished differently and they were compared to specimens with a grinded surface. The research shows that the structural elements whose surface has been burnished can have up to 30% higher fatigue strength in a seawater environment than the elements whose surface has been grinded. During burnishing, an important feature of the process is the degree of cold rolling of the material. The resistance of the component to fatigue loads increases only to a certain level with increasing the degree of the cold rolling. Further increasing the degree of cold rolling reduces the fatigue strength. Introducing additional stresses in the components (e.g., assembly stresses) reduces the fatigue strength of this component in operation and these additional stresses should be accounted for while planning the degree of the cold rolling value. A device that allows for simultaneous turning and shaft burnishing with high slenderness is presented in the appendix of this article. This device can be connected to the computerized numerical control system and executed automatic process according to the machining program; this solution reduces the number of operations and cost in the process.

Phosphate coated zinc commercial plates (Anthra-Zinc®) have been processed by laser ablation in the nanosecond pulsed regime varying the repetition rate at 10, 20 and 50 kHz. Phosphate coating was completely characterized. By monitoring the fluence it was possible to define three different processing regimes: phosphate ablation (up to 116 J/cm2), zinc ablation (up to 288 J/cm2) and zinc melting (at 375 J/cm2). 3D profilometry was used to assess both the roughness and depth parameters corresponding to each regime. The brightness was estimated from 450 to 800 nm by reflectance studies. Consequently, a long-lasting grey scale was attained envisaging in- and outdoor decorative uses. [ABSTRACT FROM AUTHOR]

Field emission is one of the critical issues in the superconducting radio frequency (SRF) cavities and can degrade their accelerating gradient during operation. The contamination present at top surface of the SRF cavity is one of the foremost reasons for field emission. Plasma based surface processing can be a viable option to eliminate such surface contaminants and enhance performance of the SRF cavity especially for in-situ applications. These days, 1.3 GHz nine-cell SRF cavity has become baseline standard for many particle accelerators, it is of interest to develop plasma cleaning technique for such SRF cavities. In the development of the plasma processing technique for SRF cavities, the most challenging task is to ignite and tune the plasma in different cells of the SRF cavity. At Daresbury laboratory, UK, we have successfully achieved plasma ignition in different cells of a 1.3 GHz nine-cell SRF cavity. The plasma ignition in different cells of the cavity was accomplished at room temperature towards room temperature plasma cleaning of the SRF cavity surface. Here, we report the successful demonstration of the plasma ignition in different cells of a 1.3 GHz nine-cell SRF cavity. [ABSTRACT FROM AUTHOR]

We present a portable, simple-to-operate, point-of-use analyte surface localization device. We take advantage of a set of hydrodynamic design features and components that achieve passive analyte localization by means of a single vacuum input. The vacuum source can be supplied by mechanical or battery-operated vacuum sources that are portable and allow point-of-use operation in the absence of electricity. We discuss the governing hydrodynamic principle and design parameters in detail. In a case study, we demonstrate the applicability of our technology through successful localization of a solution of rhodamine on a polydimethylsiloxane (PDMS) substrate and production of sub-millimetre-sized spots via application of a mild vacuum level of less than -10 kPa. In addition, using our devised technology, we demonstrate localized staining of human breast cancer cell blocks and human breast cancer tissue sections. [ABSTRACT FROM AUTHOR]

The identification of highly sensitive materials able to combine performance stability, relatively low cost, controllable and large area fabrication process is still a major bottleneck in the scientific community. Dopamine is considered a key indicator to monitor cardio and cerebrovascular diseases and its redox activeness makes electrochemical detection the most straightforward and promising sensing approach. Here we report the realization, by a simple yet effective approach, of diamond-based electrodes with a native selectivity towards dopamine. In details, three different substrate pretreatments, i.e., lapping, electropolishing and chemical etching, are adopted to tailor the morphological, structural, and sensing features of titanium doped diamond layers. SEM, AFM, Raman spectroscopy, XRD, XPS and I-V analyses demonstrate the features' modulation of the diamond layers being crucial for electrochemical and sensing performances, as confirmed by dopamine selectivity under ascorbic and uric acid interferents' excess. Furthermore, the controlled introduction of oxygen-containing groups enhances the dopamine sensitivity, lowering the detection limit from 6000 to 600 nM. In addition to giving an important insight on the physical-chemical growth processes, these preliminary results pave the way for the exploitation of these materials in a wide range of sensing applications, thanks to the non-toxicity and high surface tunability without post-synthesis treatments. • CVD-grown electroconductive Ti-doped diamond for assembling electrodes • Ti substrates' pretreatments modulate the surface properties of Ti-doped diamond. • Selectivity grade towards dopamine in PBS under the presence of interferent agents • Controlled introduction of functional groups to enhance the dopamine sensitivity [ABSTRACT FROM AUTHOR]