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This paper aims to investigate the effect of centrifugal disk finishing (CDF) technique on the surface and subsurface characteristics of the fused deposited modeling (FDM) parts in both theoretical and experimental aspects. From theoretical aspect, a novel theoretical model is developed as a function of layer deposition orientation, layer thickness, finishing working time, density ratio and hardness ratio to estimate the surface roughness profile of FDM part at different finishing conditions and finishing time intervals. Meanwhile, from the experimental aspect, an experimental campaign was performed under different mechanical and mechanical-chemical finishing conditions to verify the theoretical model and also assess the surface and subsurface characteristics of the polished parts.

The theoretical model commences with an approximation of surface profile of the FDM part through a sequence of parabola arcs, continues with the calculation of reference line and machined surface profile and leads to a formulation of surface roughness of as-printed and polished surface. In the experimental section, the FDM parts are polished under dry, pure water, 25% and 50% volumetric aqueous acetone solutions finishing conditions through CDF technique.

The comparison between experimental and theoretical results reveals 9% mean absolute error between theoretical and experimental results. Meanwhile, Rq reduction percentage of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 66.1%, 54.5%, 56.9% and 67.2%, respectively. The scanning electron microscopy results reveal severe layer damage in dry finishing condition, while the application of 50% aqueous acetone as a polishing solution completely eliminates layer damage. Another promising finding was sticky material phenomenon on the surface of polished part under 25% finishing condition. The Shore hardness test illustrates that the surface hardness improvement of the polished parts under dry, pure water, 25% and 50% aqueous acetone solutions finishing conditions are 8.4%, 2.25%, 4.36% and 10.8%, respectively. The results also revealed that the dimension variation of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 0.634%, 0.525%, 0.545% and 0.608%, respectively. The edge profile radius of the as-printed part is 134 µm, while the edge profiles radius of the polished parts under dry, pure water, 25% aqueous acetone solution and 50% aqueous acetone solution are 785.5 µm, 545.5 µm, 623.5 µm and 721.5 µm, respectively, at the polishing time of 720 min.

This paper fulfills an identified need to study the benefits of the mechanical-chemical polishing technique in comparison to mechanical and chemical polishing strategy of the FDM parts for the first time. Beside the experimental campaign, the novel analytical formulation of surface roughness as a function of mechanical properties of abrasive media and FDM part and finishing specifications provides a valuable insight in the case of material-removal processes.

In this introductory article a general survey is given of the corrosion problems facing food packers and canners. This is a large subject entailing many processes and materials and having technological aspects which sometimes find common ground only in the overriding importance of corrosion prevention. A look is given here at many of these aspects; biochemical and physiological data being supplied where necessary.

The purpose of this paper is to explore the application of triglycidyl resin (TGC) prepared from cardanol as partial replacement of conventional bis-phenol A (BPA) based epoxy resin for zinc rich primers (ZRPs).

The synthesis of new platform chemicals that are based on renewable resources has been accepted as a strategy to contribute to sustainable development due to the anticipated depletion of fossil oil reserves and rising oil prices. We prepared a tri-functional epoxy resin from cardanol which can be used as partial replacement of BPA based epoxy. The ZRPs were prepared using 50:50 ratio of TGC:BPA epoxy, and the coatings were evaluated for mechanical, chemical and anticorrosive properties.

The 50 per cent replacement of BPA based epoxy by TGC resulted in at par mechanical, chemical and anticorrosive properties as evaluated by various methods. The successful implementation can thus contribute to sustainable development by “green chemistry” route.

The prepared TGC resin in the current work was studied for application in ZRPs. This can also be explored for high performance coatings, adhesives and other engineering applications.

The TGC binder was prepared by simple two-step reaction. This can successfully be used as binder for coating application without any modifications.

A novel approach of using green and ecofriendly TGC resin as replacement of high cost BPA based epoxy was explored and can be implemented for numerous applications.

Epoxy acrylate which is commercially utilized for UV curable coatings although has excellent adhesion, flexibility, hardness and chemical resistance, they lack in antimicrobial properties. Citric acid (CA) is economical as well as a bio-based compound which possess an antimicrobial activity. So, the purpose of this research investigation is the preparation of CA-based oligomer which can be further incorporated with epoxy acrylate and tri (propylene glycol) Diacrylate (TPGDA) to form uv curable coating and the study of its antimicrobial property.

A UV-curable unsaturated oligomer (CUV) was synthesized from CA and glycidyl methacrylate (GMA). The chemical structure of CUV was confirmed by FTIR, ¹H NMR, GPC, hydroxyl value, acid value and iodine value. Further, CUV was assimilated as an antimicrobial as well as crosslinking agent to copolymerize with epoxy acrylate oligomer and a series of UV-cured antimicrobial coatings were concocted by employing UV-curing machine. The consequence of varying the fraction of CUV on the mechanical, chemical, thermal and antimicrobial properties of UV-cured wood coatings was explored.

Results exhibited good mechanical, chemical and thermal properties. In addition, it was perceived that the zone of inhibition against S. aureus got enlarged with increasing content of CUV in the coating formulation.

The synthesized bio-based CUV reveals an extensive potential to ameliorate the antimicrobial properties of UV-curable coatings.

Increasing utilisation of the properties of hardness, corrosion resistance and electrical insulation has taken place rapidly in recent years. Still scope exists for further development of anodised aluminium as knowledge of the mechanism involved grows. In the first of this two‐part article the author deals mainly with bright and conventional architectural anodising.

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.

This paper aims to evaluate the influence of molybdenum disulfide (MoS₂) concentrations (5, 7.5, 10, 12.5 and 15 Wt.%) on the microstructure and tribological property of the self-lubrication cubic boron nitride (CBN) abrasive composites.

Three point bending method and rotating sliding test are used to evaluate the flexural strength and tribological property of self-lubricating CBN abrasive composites. Microstructure, wear morphology of the ball and scratch are supported by scanning electron microscopy, optical microscope and three-dimensional confocal microscopy, etc.

The MoS₂ concentration has a significant influence on the interface microstructure between CBN abrasives and matrix alloys, and thus, affects the flexural strength of CBN abrasive composites. The grain fracture modes of CBN abrasive composites are transformed from the transgranular fracture into intergranular fracture as the MoS₂ concentrations increase. Additionally, the friction coefficient of as-sintered samples decreases with the MoS₂ concentrations. The MoS₂ concentrations of 10 Wt.% are final determined to fabricate self-lubricating composites in basis of the mechanical and lubricating property.

The ball is fabricated under vacuum sintering process. The tribological property of self-lubricating CBN abrasive composites is evaluated in terms of the friction coefficient and morphologies of the ball and scratches after rotating sliding tests.

Paint as an anticorrosive. Results depend on the preparation of the surface and on the quality of the paint. Investigations are described into the adhesive and weathering qualities of various materials, in particular of aluminium, exposing the test panels to both land and sea air. Degreasing and mechanical, chemical and electrolytical methods of cleaning the surface have been tried and compared and primers of a large variety have been tested. The primers consist of zinc chromates, phosphates and synthetics. Top coats of glycerophthalic, nitrocellulosic and other, for instance, fatty, combinations have been applied. Anti‐fouling paints have been applied to wood. It is shown that best results are obtained when the various treatments are harmonised.—(A. Guilhaudis and R. Bourbon, Revue de l'Aluminium, 1954, 31 (206), 7–11 and (207) 47–52.)

This paper aims to reveal the tribochemical reaction mechanism on the nano-cutting interface between HMX crystal and diamond tool.

Molecular dynamics simulation of HMX crystal nano-cutting by the reactive force field is carried out in this paper. The affinity of activated atoms and friction damage at the different interface have been well identified by comparing two cutting systems with diamond tool or indenter. The analyses of reaction kinetics, decomposition products and reaction pathways are performed to reveal the underlying atomistic origins of tribocatalytic reaction on the nano-cutting interface.

The HMX crystals only undergo damage and removal in the indenter cutting, while they appear to accelerate thermal decomposition in the diamond cutting. the C-O affinity is proved to be the intrinsic reason of the tribocatalytic reaction of the HMX-diamond cutting system. The reaction activation energy of the HMX crystals in the diamond cutting system is lower, resulting in a rapid increase in the decomposition degree. The free O atoms can induce the asymmetric ring-opening mode and change the decomposition pathways, which is the underlying atomistic origins of the thermal stability of the HMX-diamond cutting system.

This paper describes a method for analyzing the tribochemical behavior of HMX and diamond, which is beneficial to study the thermal stability in the nano-cutting of HMX.

The purpose of this paper is to discuss the opportunities and challenges of mass customisation (MC), together with the possibilities for enablement using the technologies of rapid manufacturing (RM).

A thorough evaluation of numerous approaches to RM of customised products is presented, with particular focus on relative advantages and limitations of each technology. To demonstrate the applicability of specific techniques, case studies from both consumer and medical applications are reported based on original research.

The paper highlights not only the opportunities for RM technologies, but also the limitations of specific processes. This approach provides guidance for practitioners in the selection of appropriate technologies for MC enablement.

The focus of this practitioner review is limited to proprietary RM materials and systems which are already commercially available, with relatively little attention given the technologies presently in development.

Whilst RM and MC have already received much attention in the literature, comparatively little consideration has been given to the unification of both concepts. This paper has particular emphasis on this unification with respect to the selection of appropriate technologies, and presents an appraisal of existing applications making use of RM. Through this approach, practitioners gain information in the selection of appropriate technologies for MC.