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The purpose of this paper is to build a transient wear prediction model of surface topography of textured work roll, and then to investigate the wear performance of different original textured surfaces. The surface topography of steel sheets is one of the most important surface quality indexes, which is inherited from the textured work rolls in cold rolling. Surface topography of work roll is obviously changing in the cold rolling process. However, surface topography is difficult to measure in the industry production process.

This paper presents a numerical approach to simulate the wear process based on the mixed lubrication model of cold rolling interface developed by Wilson and Sheu (Sheu and Wilson, 1994). It is assumed that wear takes place at locations where the surfaces are in direct contact, and the volume is removed by an abrasive particle which is an abstract concept based on the wear phenomenon of textured work roll. At each simulation cycle, the distribution of the contact pressure is calculated by the lubrication model. The material is removed by an abstract abrasive particle and the surface topography is modified correspondingly. The renewed surface topography is then used for the next cycle.

Through comparative analysis, it can be found that the simulation results possess similar statistical characteristic with the measured data. A set of roughness parameters such as the amplitude, spacing and frequency-domain characteristics are introduced to analyze the wear performance of different textured surfaces. Numerical examples show that the surface topography has a significant effect on the wear performance of work roll in cold rolling.

The proposed model can accurately predict the wear process of the surface topography in the cold rolling process, which provides the foundation for optimization of original surface topography of textured work roll. The model can also be considered as a tool applicable for research on control of the surface topography of steel strip in the cold rolling process.

Three-dimensional (3D) printed parts usually have poor surface quality due to layer manufacturing’s “stair casing/stair-stepping”. So post-processing is typically needed to enhance its capabilities to be used in closed tolerance applications. This study aims to examine abrasive flow finishing for 3D printed polylactic acid (PLA) parts.

A new eco-friendly abrasive flow machining media (EFAFM) was developed, using paper pulp as a base material, waste vegetable oil as a liquid synthesizer and natural additives such as glycine to finish 3D printed parts. Characterization of the media was conducted through thermogravimetric analysis and Fourier transform infrared spectroscopy. PLA crescent prism parts were produced via fused deposition modelling (FDM) and finished using AFM, with experiments designed using central composite design (CCD). The impact of process parameters, including media viscosity, extrusion pressure, layer thickness and finishing time, on percentage improvement in surface roughness (%ΔRa) and material removal rate were analysed. Artificial neural network (ANN) and improved grey wolf optimizer (IGWO) were used for data modelling and optimization, respectively.

The abrasive media developed was effective for finishing FDM printed parts using AFM, with SEM images and 3D surface profile showing a significant improvement in surface topography. Optimal solutions were obtained using the ANN-IGWO approach. EFAFM was found to be a promising method for improving finishing quality on FDM 3D printed parts.

The present study is focused on finishing FDM printed crescent prism parts using AFM. Future research may be done on more complex shapes and could explore the impact of different materials, such as thermoplastics and composites for different applications. Also, implication of other techniques, such as chemical vapour smoothing, mechanical polishing may be explored.

In the biomedical field, the use of 3D printing has revolutionized the way in which medical devices, implants and prosthetics are designed and manufactured. The biodegradable and biocompatible properties of PLA make it an ideal material for use in biomedical applications, such as the fabrication of surgical guides, dental models and tissue engineering scaffolds. The ability to finish PLA 3D printed parts using AFM can improve their biocompatibility, making them more suitable for use in the human body. The improved surface quality of 3D printed parts can also facilitate their sterilization, which is critical in the biomedical field.

The use of eco-friendly abrasive flow finishing for 3D printed parts can have a positive impact on the environment by reducing waste and promoting sustainable manufacturing practices. Additionally, it can improve the quality and functionality of 3D printed products, leading to better performance and longer lifespans. This can have broader economic and societal benefits.

This AFM media constituents are paper pulp, waste vegetable oil, silicon carbide as abrasive and the mixture of “Aloe Barbadensis Mill” – “Cyamopsis Tetragonoloba” powder and glycine. This media was then used to finish 3D printed PLA crescent prism parts. The study also used an IGWO to optimize experimental data that had been modelled using an ANN.

The purpose of this present work is to investigate how different parameters of the blast cleaning process affect properties and quality of brass parts surface. It aims to study the following process variables: particle abrasive shape: (spherical (S) and angular (G) shot), particle abrasive size (S170, G40 and G50) and the impact velocity (40 m/s, 60 m/s and 80 m/s).

An experimental approach based on three testing methods is used to quantify the analysis of particulate contaminants on substrates surfaces. These methods are: SEM, BSEM and EDXA plots from SEM imaging.

The results obtained clearly show that the particle embedment decreases with decreasing of the size of angular abrasive. An increase in the embedment could be noted as impact velocity increased. It was also found that the angular abrasives have delivered a contamination level higher than that delivered by spherical abrasives. Furthermore, it was demonstrated that the abrasive debris nature embedded in the treated surfaces is the iron. The coupling of this debris with the base metal (copper) in the presence of wetland causes an electrochemical corrosion. Then, if the contamination level decreases, the corrosion rate in treated brass parts by steel shots decreases also.

Search in the case of blast cleaning for the brass parts by steel shots has not been done previously. Using the spherical shape of the abrasive projected with a moderate impact velocity will be a solution in this case.

The purpose of this paper is to use a wear test to determine the effect of sand on the wear rates of materials typically used in aerospace applications. Once a repeatable wear test has been established, it can be used to test any combination of materials or coatings. The effectiveness of several different test methods will also be evaluated, including the sample height, surface roughness and mass difference. In addition, the current work will observe the differences between applying sand before the samples are brought into contact or after. The wear rates obtained from these tests could also be used to predict the wear of other components in similar abrasive particulate environments.

A modified block-on-flat wear test of anodized aluminum on hard coat anodized aluminum was used to study this. The experiments were performed with and without sand to study the effects of the sand. Two methods of adding sand were also evaluated. Weighing and profilometry were used to study the differences between the tests.

Wear rates have been calculated based on both the change in the masses of the samples and the change in the height between the upper and lower samples over the course of each test. The wear rates from the change in the masses are repeatable with and without sand, but the results for the change in height show no repeatability without sand. In addition, only in the presence of sand do the trends for the two methods agree. The wear rate was found to be non-linear as a function of load and therefore not in agreement with Archard’s Wear Law. The wear rate also increased significantly when sand was present in the contact for the duration of the test. The sand appears to change the wear mechanism from an adhesive to an abrasive mechanism. Black wear particles formed both when there was sand and when there was not sand. The source of these particles has been investigated but not determined.

This work has not been previously published and is the original work of the authors.

This paper aims to validate an axial turbine modified nozzle design, looking for a reduction of the nozzle erosion process during operation in power plants.

The approach taken is numerical simulation using the computational fluid dynamics (CFD) tool, comparing original and proposed/modified nozzle designs.

The paper provides information about how to achieve a solution of the turbine operational problem (abrasive wear) by an analysis of flow patterns under a variety of conditions.

It does not give a detailed interpretation of flow behaviour due to the lack of validation data.

A very useful flow simulation methodology that can be used in industry is provided.

The proposed design modification of an axial turbine nozzle with the aid of CFD simulation has not been performed yet. This paper investigates the possibility of nozzle erosion reduction by modifying local flow patterns.

A method extensively used in the production of optically flat and finely finished surfaces is that of lapping the surface upon a plate using a loose abrasive mixed into a slurry form with a carrying fluid. If the surfaces finished in this way are in continuous or intermittent sliding contact, it is the author's opinion that any abrasives retained in their surfaces will affect surface wear. This paper reported on some exploratory work to indicate the degree of embedment of abrasive in certain materials lapped by hand.

WEAR is one of the major ways by which a material part ceases to be useful, others are corrosion, obsolescence and breakage. It is the consequence of relative motion and in industrial plant and equipment it has always been accepted as inevitable that it should lead to heavy expenditure for maintenance and replacement. Historically, wear is a well established fact, yet our knowledge of the technology is extremely limited. It has become a way of life that we compensate for wear when it no longer can be tolerated, yet need this be so? This article examines the problem, and primarily from the unlubricated point of view, describes the various types of wear and the way material selection or modification can be used to limit wear.

This paper aims to report the effect of titanium oxide (TiO₂) particles on the physical, mechanical, tribological and water resistance properties of 5% NaOH-treated bamboo fiber–reinforced composites.

In this research, the epoxy/bamboo/TiO₂ hybrid composite filled with 0–8 Wt.% TiO₂ particles has been fabricated using simple hand layup techniques, and testing of the developed composite was done in accordance with the American Society for Testing and Materials (ASTM) standard.

The results of this study indicate that the addition of TiO₂ particles improved the mechanical properties of the developed epoxy/bamboo composites. Tensile properties were found to be maximum for 6 Wt.%, and impact strength was found to be maximum for 8 Wt.% TiO₂ particles-filled composite. The highest flexural properties were found at a lower TiO₂ fraction of 2 Wt.%. Adding TiO₂ filler helped to reduce the water absorption rate. The studies related to the wear and friction behavior of the composite under dry and abrasive wear conditions reveal that TiO₂ filler was beneficial in improving the wear performance of the composite.

This research paper attempts to include both TiO₂ filler and bamboo fibers to develop a novel composite material. TiO₂ micro and nanoparticles are promising filler materials; it helps to enhance the mechanical and tribological properties of the epoxy composites and in literature, there is not much work reported, where TiO₂ is used as a filler material with bamboo fiber–reinforced epoxy composites.

The purpose of this paper is to investigate the effect of a vibratory bed, as an assistant agent, on the improvement of the drag finishing process. The dynamics and kinematic of the process were surveyed in microscale for different frequencies and amplitudes and the results were compared to the basic process.

The discrete element tool was used to find out the effect of the vibratory bed on the drag finishing process. To this end, the Hertz-Mindlin model was used to investigate the contact of abrasive particles and workpiece. At the first stage, the numerical model was validated with the experimental results, and then the effect of different parameters on the finishing process was evaluated and compared with the basic case.

The chosen numerical model was in good agreement with the results measured in the previous literature. Moreover, the results show that not only vibrated bed enhances the contacts of abrasive particles to the workpiece, but it also increases the uniformity of the finished surface.

In comparison to the experiments, the discrete element technique consumes lower cost and time to estimate the optimum conditions of the finishing process, as well as it provides a good understanding of this phenomenon on the micro-scale.

The goal of this study is to determine the values of the process parameters that should be used during the machining of ceramic tile using the abrasive water jet (AWJ) process in order to achieve the lowest possible values for surface roughness and kerf taper angle.

In the present work, ceramic tile is processed by the AWJ process and experimental data were recorded using the RSM approach based Box–Behnken design matrix. The input process factors were water jet pressure, jet traverse speed, abrasive flow rate and standoff distance, to determine the surface roughness and kerf taper angle. ANOVA was used to check the adequacy of model and significance of process parameters. Further, the elite opposition-based learning grasshopper optimization (EOBL-GOA) algorithm was implemented to identify the simultaneous optimization of multiple responses of surface roughness and kerf taper angle in AWJ.

The suggested EOBL-GOA algorithm is suitable for AWJ of ceramic tile, as evidenced by the error rate of ±2 percent between experimental and predicted solutions. The surfaces were evaluated with an SEM to assess the quality of the surface generated with the optimal settings. As compared with initial setting of the SEM image, it was noticed that the bottom cut surface was nearly smooth, with less cracks, striations and pits in the improved optimal results of the SEM image. The results of the analysis can be used to control machining parameters and increase the accuracy of AWJed components.

The findings of this study present an innovative method for assessing the characteristics of the nontraditional machining processes that are most suited for use in industrial and commercial applications.