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The purpose of this paper is to study the functionality of additively manufactured (AM) parts, mainly depending on their dimensional accuracy and surface finish. However, the products manufactured using AM usually suffer from defects like roughness or uneven surfaces. This paper discusses the various surface quality improvement techniques, including how to reduce surface defects, surface roughness and dimensional accuracy of AM parts.

There are many different types of popular AM methods. Unfortunately, these AM methods are susceptible to different kinds of surface defects in the product. As a result, pre- and postprocessing efforts and control of various AM process parameters are needed to improve the surface quality and reduce surface roughness.

In this paper, the various surface quality improvement methods are categorized based on the type of materials, working principles of AM and types of finishing processes. They have been divided into chemical, thermal, mechanical and hybrid-based categories.

The review has evaluated the possibility of various surface finishing methods for enhancing the surface quality of AM parts. It has also discussed the research perspective of these methods for surface finishing of AM parts at micro- to nanolevel surface roughness and better dimensional accuracy.

This paper represents a comprehensive review of surface quality improvement methods for both metals and polymer-based AM parts.

This paper aims to focus on the changes in thermal and surface characteristics of acrylonitrile butadiene styrene (ABS) material when exposed to chemical vapours for surface finishing. The poor surface finish and the dimensional accuracy of the fused deposition modelling parts (of ABS material) because of the stair-stepping hinder their use for rapid tooling applications, which can be improved by vapour finishing process. The differential scanning calorimetry (DSC) tests are performed to investigate the thermal behaviour of ABS thermoplastic after vapour finishing.

The hip prosthesis replica has been used to highlight the efficacy of chemical finishing process for intricate and complex geometries. The replicas are treated with chemical vapours for different durations. The DSC tests are performed along with surface roughness, surface hardness and dimensional measurements of exposed replicas and compared with unexposed replica.

The longer finishing time, i.e. 20 s, manifested higher melting peak temperature, higher melting enthalpy and higher heat capacity along with smoother and harder surface as compared with unexposed replica. The finishing process enhanced the bonding strength and the heat-bearing capacity of ABS material. The vapour finishing process enhanced the thermal stability of the material which may extend its sustainability at higher temperatures.

The improved thermal stability of ABS thermoplastic after chemical vapour finishing has been demonstrated. This advancement allows the use of ABS in functional tooling suitable for small production runs with higher flexibility and lead time savings.

The heat effects associated with phase transitions as a function of temperature are studied in case of replicas finished with chemical vapours. The relationship between melting enthalpy and surface characteristics has been ascertained.

Some of the basic mechanical characteristics such as tensile, bending, shear, compression, and surface properties of cotton knitted fabrics after a durable flame‐retardant finishing, were studied by the objective‐evaluation method developed by Kawabata and Niva using the KES‐F system. In addition, properties such as bursting strength, drape and sewability were studied in order to further explore the influence of this treatment on the fabrics. All treated fabrics were flame‐retardant but their mechanical properties showed changes as a result of the above finishing. More specifically, a significant reduction in the bending and shear properties was recorded, which suggests that the flame‐retardant finishing primarily affects the above characteristics.

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.

Additive manufacturing (AM) has the potential to revolutionise the fabrication of complex surgical instruments. However, AM parts typically have a higher surface roughness compared to machined or fine cast parts. High surface roughness has important implications for surgical instruments, particularly in terms of cleanliness and aesthetic considerations. In this study, bulk surface finishing methods are described to produce end-use selective laser melting parts.

The aim was to achieve a surface finish as close as possible to machined parts (Ra = 0.9 µm, Wa = 0.2 µm, Pv = 7.3 µm). A sample coupon was designed to systematically evaluate different finishing techniques. Processes included bulk finishing, blasting and centrifugal finishing methods on individual parts, as well as heat treatment before and after surface finishing.

Abrasive blasting or centrifugal finishing alone was not adequate to achieve an end-use surface finish. White oxide vapour blasting at high water pressure was the most effective of the abrasive blasting processes. For centrifugal finishing, a 4 h runtime resulted in an acceptable reduction in surface roughness (Ra = 2.9 µm, Wa = 2.0 µm, Pv = 34.6 µm: inclined surface [30°]) while not significantly increasing part radii. The combination of finishing methods resulting in the smoothest surfaces was white oxide blasting followed by 4 h of centrifugal finishing and a final glass bead blast (Ra = 0.6 µm, Wa = 0.9 µm, Pv = 6.9 µm: inclined surface [30°]). The order of these methods was important because white oxide blasting was significantly less effective when applied after the centrifugal finishing.

Collectively, these results describe the development of a practical bulk finishing method for stainless steel surgical instruments produced by AM.

The purpose of this paper is to provide a review of finishing robot technology and its applications.

The paper initially considers the development of automated finishing technologies and then discusses robotic systems. The uses of robotic finishing are illustrated through reference to a range of applications and case histories and a final section summarises the key benefits of the technology.

The paper shows that robotic finishing is being adopted by a range of industries including the aerospace, automotive, medical and household goods sectors. The technology has been shown to yield significant benefits, notably improved productivity, cost reductions, more consistent quality and reduced reject levels.

The paper provides a useful insight into robotic finishing and illustrates the key applications and benefits of the technology.

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 assess the relationships amongst the tearing strength of fabrics after each chemical processing stage and after finishing of plain-woven cotton fabric. An effort has been made to study the effect of different finishing chemicals (tear improver) and their different concentrations on the high-density fabric tear strength and its sub-component with respect to the co-efficient of friction value of yarns for all the fabric samples. It also aims to establish a statistical model for prediction of tear strength with identified parameters as yarn–yarn friction co-efficient, yarn pullout force and single yarn strength.

In case of woven fabrics, it cannot be assumed that only yarn friction plays the role in deciding fabric-tearing strength. Whether the static or kinetic frictions need to be considered or the linear or capstan frictions have to be analyzed, to incorporate the results of friction analysis in the tearing behavior, need to be assessed. In the present work through a fabrication of yarn–yarn friction measurement, under a synchronized slow speed as that of actual fabric tearing (50 mm/min), has been carried out. After each wet processing stage, surface characteristics of yarns have been changed. Surface of yarns becomes smoother after finishing and rough after dyeing, which affects the co-efficient of friction of yarns, accordingly.

After each wet processing stage, the surface characteristics of yarns are changed. Surface structure of yarns becomes smooth after finishing and rough after dyeing, which affects the co-efficient of friction of yarns. For all the fabrics, the weft-way tearing strength is always higher than warp-way tearing strength. It is also observed that yarn pullout force is not the only responsible factor for tearing strength of such fabric. It is because of the combined action of yarn–yarn friction, yarn pullout force and single yarn strength for a given structure.

A more extensive investigation with respect to concentration as well as further variety of chemicals requires to be identified for the optimum concentration level for each chemical. A mathematical model based on the three parameters as yarn–yarn co-efficient of friction, yarn pullout force and yarn strength for all woven fabric structure to achieve optimum strength level has been established which could be further extended for each fabric structures.

The problem has been identified from the day-to-day exercise of the commercial textile industry. The whole of the sample preparations have been done in the industry by using commercial machines under standard industrial conditions. The findings have been discussed and suitably introduced in the industry.

The whole of this paper has been unique in idea origination, sample preparation and execution of tests. The findings are very important for the researchers as well as for textile industry.

Naturally colored cotton (NCC) based wovens are finished with 1,2,3,4-butanetetracarboxylic acid (BTCA), which is an environmentally friendly durable press (DP) finish. The colors of the NCC wovens before and after DP finishing are examined. The color fastnesses to home laundering and light irradiation are compared and evaluated. The DP finishing of BTCA has a negative effect on the color of NCC based fabrics. About 1/3 of the shade depth of the NCCs are decreased after a BTCA finishing. For both the fabrics with and without a DP finishing, home laundering results in evident color changes with decrease of shade depth. However, for probable crosslinking to pigments, a DP finishing could significantly improve the home laundering color fastness of NCCs. The performance of the color fastness to light after a BTCA finishing depends on the cotton breed. The BTCA finishing of the green NCC minimally improves the light fastness, while for the brown NCC, the color fastness to light decreases after the BTCA finishing.

The surface roughness of additively manufactured parts is usually found to be high. This limits their use in industrial and biomedical applications. Therefore, these parts required post-processing to improve their surface quality. The purpose of this study is to finish three-dimensional (3D) printed acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) parts using abrasive flow machining (AFM).

A hydrogel-based abrasive media has been developed to finish 3D printed parts. The developed abrasive media has been characterized for its rheology and thermal stability using sweep tests, thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The ABS and PLA cylindrical parts have been prepared using fused deposition modeling (FDM) and finished using AFM. The experiments were designed using Taguchi (L9 OA) method. The effect of process parameters such as extrusion pressure (EP), layer thickness (LT) and abrasive concentration (AC) was investigated on the amount of material removed (MR) and percentage improvement in surface roughness (%ΔR_a).

The developed abrasive media was found to be effective for finishing FDM printed parts using AFM. The microscope images of unfinished and finished showed a significant improvement in surface topography of additively manufactures parts after AFM. The results reveal that AC is the most significant parameter during the finishing of ABS parts. However, EP and AC are the most significant parameters for MR and %ΔR_a, respectively, during the finishing of PLA parts.

The FDM technology has applications in the biomedical, electronics, aeronautics and defense sectors. PLA has good biodegradable and biocompatible properties, so widely used in biomedical applications. The ventilator splitters fabricated using FDM have a profile similar to the shape used in the present study.

The present study is focused on finishing FDM printed cylindrical parts using AFM. Future research may be done on the AFM of complex shapes and freeform surfaces printed using different additive manufacturing (AM) techniques.

An abrasive media consists of xanthan gum, locust bean gum and fumed silica has been developed and characterized. An experimental study has been performed by combining printing parameters of FDM and finishing parameters of AFM. A comparative analysis in MR and %ΔR_a has been reported between 3D printed ABS and PLA parts.