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Optical profilometry has many industrial uses, from machine tool measurements to microelectronics, as experts explain.

The purpose of this paper is to investigate and find out the surface and electrochemical behaviours of twin roll cast (TRC) 8006 aluminium alloy with different thicknesses due to the cold rolling rates after the TRC process.

The 8006 aluminium alloys are mostly used for the food packaging industry, as they are corrosion resistant, lightweight and shapable materials. The present work investigates the surface and corrosion behaviours of 8006 aluminium alloys at different thicknesses. TRC aluminium alloys were cold-rolled at two different reduction rates before investigation. X-ray diffraction (XRD) and energy dispersive spectroscopy (EDX) tests were used to examine the phase and elemental analyses. FE-SEM and 3D profilometry also used to observe surface morphology. Open circuit potential (OCP), potentiodynamic polarization and electrochemical impedance spectroscopy tests (EIS) were carried out to find out corrosion behaviours. The results show that the more cold rolling reduction (CRR), the more corrosion rate and surface affection of the TRC 8006 aluminium alloys.

According to the electrochemical tests (OCP, potentiodynamic polarization test and EIS) and surface morphology results (such as SEM, 3D profilometry and XRD) the more the rolling rate the less the corrosion resistance.

First corrosion behaviour investigation of twin-rolled 8006 Al alloys using electrochemical techniques. First investigation of CRR effects on electrochemical corrosion behaviour of 8006 Al alloys with 3.5 wt.% NaCl solution using EIS. First investigation of 8006 Al alloys as a food packaging material with electrochemical ways.

Even though copper–tungsten has shown signs of potentials, relatively little is currently known about its appropriateness for photovoltaic application. This paper aims to evaluate the suitability of copper-tungs oxides as photovoltaic absorbers while investigating the consequences of oxygen content variation.

Using profilometry, Hall measurements, Seebeck test and spectrophotometry, grown samples were defined. Samples of 5 standard cubic centimeters per minute (sccm) and 7 sccm exhibited appropriate characteristics and were further tested using personal computer one dimension (PC1D) computational simulation at the system stage. To grow materials with an average thickness below 0.45 µm, magnetron co-sputtering was used. Three sample sets, varied by oxygen flow rate, were made with flow rates of 5sccm, 7sccm and 9sccm, respectively.

Some samples proved to be effective absorbers, using a cadmium telluride device as the criterion of output calculation, with one sample chosen as ideal for each type of flow rate. For the chosen samples, an optimum thickness was also obtained, i. It was discovered that thinner cells, optimal for both groups with 0.6 µm, performed better to than other thicknesses.

The material also demonstrated prospects for applications in window layers, but more needs to be known.

Thin film material properties and their operating processes are relatively complex, so it is important to find simple and cost-effective ways to forecast performance. While relatively new, numerical modeling has proven to be very useful in defining the critical properties of thin film devices, thereby helpful for predictions of performance. Solar cell capacitance simulator one dimension, amorphous semiconductor analysis, personal computer one dimension (PC1D), analysis of micro-electronic and photonic structures and automat for simulation for heterostructures (33) are several common models in the thin film industry. Due to its availability and relative ease of use, PC1D was used in this project.

As the search for the balance among performance, cost, reliability and availability continue, more absorber components continue to evolve, notably from the chalcogenides. Because of their ability to absorb light, ternary transition metal chalcogenides are useful in the production of hydrogen and in the energy storage sector, as well as in the production of light-emitting diodes and solar photovoltaic (PV).

There are several methods for the manufacture of copper–tungsten alloys, but the process of combinatorial sputtering of magnetrons provides satisfactory results even for the manufacture of various other materials. Cu₂WSe₄, an excellent alternative to sputtering, is one of the very few copper–tungsten selenide materials tested, synthesized by hot simple injection to have strong crystallinity and lacks impurity. The optical properties of colloidal Cu₂WSe₄ show that Schottky diode–like behaviors are present in the material, suggesting its potential for use in solar cells. Cu-W alloys could have a lot more to give the PV industry, by all indications. Further exploration of the oxides by this work is thus justified. Transparent conducting oxides, interfacial layers or charge-transporting compounds are commonly used as transition metal oxides. Nevertheless, as absorbers, metal oxides such as BiFeO₃ and the traditionally highly studied Cu₂O have been tested, with Cu₂O showing a conversion efficiency of up to 10% under particular conditions. This displays strong electronic and optical properties, so there might be some possibility of studying other PV absorption metal oxides. The optical properties of colloidal Cu₂WSe₄ show that Schottky diode–like behaviors are present in the material, suggesting its potential for use in solar cells.

To examine the impact of oxide and oxide alternative processes on signal loss in commercial RF applications.

Stripline conductors were formed using traditional oxide, oxide dissolution/reduction, and oxide alternative processes. Conductor geometry was measured and surface topography was characterized. Effective dielectric constants and characteristic impedance for each system was determined. Finally, line loss for each treatment and rework condition was charted to nearly 20 GHz. Electrical measurements were performed by taking S‐parameter measurements through 20 GHz using an agilent vector network analyzer (VNA).

The methods employed were sufficient to statistically characterize the increased loss associated with thick oxides and high‐microetch oxide alternatives. Lower etch oxide alternatives yielded benefits for signal integrity. Of importance, rework procedures gave unacceptable increases in line loss. Overall, however, the loss due to innerlayer bonding processes was not of sufficient magnitude to elevate oxides as a primary contributor to conductor loss. For the relative simple, high production system employing epoxy substrate, oxide loss was found to be far less than substrate effects, imaging quality, and foil treatment.

Electrical engineers and printed circuit board (PCB) designers strive to focus their efforts on improving the PCB processes leading to maximum conductor loss in the electronic system. This work shows that oxide treatments are not a primary factor in affecting loss. Significant improvements in signal integrity may be achieved, however, with the use of low‐etch oxide alternatives and with restrictions on oxide rework. In addition, this paper allowed for new interpretations of VNA data for better modeling of PCB system data using non‐classical analysis.

The purpose of this paper is to study the effect of silicon and phosphorus content in steel suitable for galvanizing on its corrosion and inhibitor adsorption processes in steels/cetyltrimethylammonium bromide combined and KI (mixture)/5.0 M hydrochloric acid systems has been studied in relation to the temperature using chemical (weight loss), Tafel polarization, electrochemical impedance spectroscopy (EIS), scanning electronic microscope (SEM) analysis and Optical 3D profilometry characterization. All the methods used are in reasonable agreement. The kinetic and thermodynamic parameters for each steels corrosion and inhibitor adsorption, respectively, were determined and discussed. Results show that the adsorption capacity for Steel Classes A and B are better than Steel Class C surfaces depending on their silicon and phosphorus content. Surface analyses via SEM and Optical 3D profilometry was used to investigate the morphology of the steels before and after immersion in 5.0 M HCl solution containing mixture. Surface analysis revealed improvement of corrosion resistance of Steels Classes A and B in the presence of mixture more than Classes C. It has been determined that the adsorbed protective film on the steels surface heterogeneity markedly depends on steels compositions, that is, the heterogeneity increases with decreasing silicon and phosphorus content.

The effect of silicon and phosphorus content in Steels Classes A, B and C on its corrosion and inhibitor mixture adsorption processes in 5.0 M HCl solution has been studied by weight loss, potentiodynamic polarization, EIS and surface analysis.

The inhibition efficiency of mixture follows the order: (Steel Class A) > (Steel Class B) > Steel Class C) and depends on their compositions in the absence of mixture according on their silicon and phosphorus content, that is, the corrosion rate increases with increasing of the silicon and phosphorus content. A potentiodynamic polarization measurement indicates that the mixture acts as mixed-type inhibitor without changing the mechanism of corrosion process for the three classes of mild steels.

Corrosion rate mild steels in 5.0 M HCl depends on their compositions in the absence of mixture according to their silicon and phosphorus content, that is, the corrosion rate increases with increasing silicon and phosphorus content. The adsorbed protective film on the steels surface heterogeneity markedly depends on steels class’s compositions, that is, the heterogeneity increases with decreasing silicon and phosphorus content.

The purpose of this paper is to outline and document the failure root cause of a carbide cutting tool during machining of a hardened tool steel under automatic machining conditions.

Optical metallography and SEM/energy dispersive spectroscopy analysis, together with optical profilometry were employed for failure investigation. The use of an alternative cutting tool and modification of machining conditions are proposed as a failure preventive action.

Severe abrasive wear and adhesion of machining chips are observed in the flank zone, causing blunting of the cutting edge. The revision of cutting conditions, together with the use CBN-based tool insert leads to an overall improvement of the stability of the process and tool lifetime.

This paper places emphasis on a failure analysis case history following a structured approach in industrial machining problem solving, highlighting suggestions for process improvement.

The purpose of this paper is to characterize polyamide parts prepared by the SLS process using techniques that are dependent on surface properties and compare the results to density measurements in order to assess which technique better reflects the degree of densification achieved using different laser power levels.

Fabrication of Nylon 12 (Duraform PA) samples and their characterization by apparent density measurements, perfilometry, Raman spectroscopy, scanning electron microscopy, specific surface area and contact angle measurements.

Methods dependent on surface analysis are not suitable indicators of the degree of sample densification. Among the surface methods, the results from Raman spectroscopy are the ones with the best performance. Incipient sintering of the superficial layers and raw material powder on the surface, inherent to the parts made by the SLS process, strongly interfere with the characterization.

Quantitative comparison of a number of surface probing methods for monitoring densification of SLS parts. Characterization of sample surfaces with and without raw material powder.

The test procedure for characterizing the tribological behavior of lubricants and materials for the system “piston ring/cylinder liner” outside of engines is now operational and validated. The test parameters presented in this paper (F_N=50 N; v=0.3 m/s, s=24 km) may act only as an indicator and should be used to the tasks regarded. It allows the check prior expensive engine testing, if a tribomaterial, tribocouple or new lubricant will reach a satisfactory engine performance. The introduction of piston ring segments and cylinder liner as specimen into the test rig as well as the volumetric wear determined by means of stylus profilometry represented a big step forward in order to increase the transferability of “tribotests” to engine tests on an acceptable level.

This study aims to investigate the friction coefficient of Al2O3–NbC nanocomposite obtained by spark plasma sintering sliding against a steel ball.

Tribological tests were carried out using a reciprocating nanotribometer in a ball on flat configuration with normal loads in the range from 10 to 100 mN under dry conditions. Surface changes were analyzed by confocal microscopy and 3D profilometry.

The values of the friction coefficient varied from 0.15 to 0.6 and are independent of the applied load.

The tribological behavior is attributed to fracture in the contact region and the effect of wear debris.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0356/

The purpose of this paper is to compare the results from mechanical testing with measurements of surface-dependent properties performed on polyamide parts made by selective laser sintering (SLS) to assess a possible correlation between them.

Fabrication of Nylon 12 (Duraform PA®) samples using different laser power levels and their characterization by tensile testing, roughness and Raman scattering measurements.

Among the surface methods investigated, the results from Raman spectroscopy are the best ones, but methods dependent on surface analysis are not really suitable as indicators of the mechanical properties. The correlation coefficients for linear fitting obtained when the normalized results of mechanical properties are plotted against the surface properties are too low. Furthermore, the ambiguity between surface and mechanical data makes it impossible to use these surface properties for prediction purposes in the industrial environment.

Quantitative evaluation and correlation between mechanical properties and surface properties of SLS-made samples.