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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.

The purpose of this paper is to study the integration between fused deposition modeling (FDM) technology and abrasive flow machining process to improve the surface quality of FDM printed parts. FDM process has some limitations in terms of accuracy and surface finish. Hence, post-processing operations are essential to increase the quality of the part.

Initially, a sustainable polymer abrasive gel-based media (SPAGM) using natural polymer and natural additives (waste vegetable oil) was prepared using different combinations of (abrasive mesh size, percentage of abrasives and percentage of liquid synthesizer); then the characterization of media was done to check various properties. As media is an essential part in the process which helps in increase the surface finish, it needs to have some desired characteristics such as the following: the developed SPAG needs to hold the abrasives; its viscosity has to be medium so that it can easily flow through the machine; and its thermal stability caused by the increase in the temperature during various cycles of operation. For that, it is characterized rheologically as well as thermally to find its various properties.

Experiments were performed on FDM-printed parts using an L9 orthogonal array with different parameters to find their effect on the workpiece. Scanning electron microscope images of SGAPM showed sharp edges of abrasive particles and bonding pattern between polymer chain molecules. Good surface finish and material removal rate (MRR) was observed at high pressure and long finishing time with 50 per cent abrasive concentration.

The authors confirm that this work is original and has neither been published elsewhere nor is it currently under consideration for publication elsewhere.

Bacterial cellulose (BC) is an ideal alternative filtering material. However, current functionalization approaches for BC have not been fully discovered industrially as well as academically applying textile processing. This study aims to create a sustainable fabric-like membrane made of BC/activated carbon (AC) for applications in filtration using textile padding method, to protect people from respiratory pandemics.

Fabric-like BC is first mechanically dehydrated then AC is loaded via a textile padding step. The finishing efficacy, properties of fabric-like BC/AC and NaOH pretreatment are analyzed and characterized by scanning electron microscope (SEM), field emission scanning electron microscope (FE SEM), X-ray diffraction (XRD), CIELab color space, color strength (K/S), nitrogen adsorption-desorption isotherm including Brunauer–Emmett–Teller (BET) specific surface area and Barrett–Joyner–Halenda (BJH) pore size and volume.

This research results in a fabric-like BC/AC with pore diameters of 3.407 ± 0.310 nm, specific surface area of 115.28 m²/g and an efficient scalable padding process, which uses 8 times less amount of chemical and nearly 30 times shorter treating duration than conventional methods.

Our globe is now consuming an alarming amount of non-degradable disposable masks resulting in massive trash buildup as a future environmental problem. Besides, current disposable masks requiring a significant upfront technological investment have posed challenges in human protection from respiratory diseases, especially for countries with limited conditions. By combining a sustainable material (BC) with popular padding method of textile industry, the fabric-like BC/AC will offer sustainable and practical values for both humankind and nature.

This research has offered an effective padding process to functionalize BC, and a unique fabric-like BC/AC membrane for filtration applications.

PROBABLY one of the most remarkable features of our generation has been the ability of the metallurgist to produce alloys meeting the current needs of industry in providing the requisite mechanical characteristics, capabilities of being manipulated or fashioned by established methods, and in particular instances, specific properties of resistance to erosion, corrosion, wear, impact and fatigue. Perhaps this adaptability is best exemplified in the case of light alloys, whereby scientific alloying of aluminium or magnesium bases with other elements, combined with specific thermal treatments, have imparted increased strength, durability, and, under limited conditions, resistance to corrosion, to a whole range of alloys without any appreciable sacrifice of the great advantage in initial lightness of these two base metals. In view of this, these metals, which are conveniently designated “light alloys,” have become exceedingly popular, particularly since the majority of them are eminently suitable for fabrication in the form of diecastings, which permit the reproducibility of exact forms in large quantity production. The mechanical features of light alloys, together with their capacity to be machined, or otherwise finished to shape and dimensions, are fairly widely known, but their ability and relative merits to resist various conditions of corrosive influence are not so clearly elucidated. The readers of this journal arc naturally concerned primarily with finishes of protective value rather than with those of decorative importance. In general engineering considerable confusion exists as to the behaviour of aluminium and its alloys under deleterious influences, and this tends to retard their general adoption, even though their individual mechanical properties may make them highly desirable. In some cases most unnecessarily elaborate finishes are applied for ultra precautionary purposes, while in others a complete ban is exercised rather than incur any risk. In the aircraft industry, on the other hand, the demand for minimum weight consistent with requisite strength has provided the impetus for their adoption, which in turn has led to the development of appropriate finishing methods. Even in this sphere a comparative survey of finishing methods and their efficiency covering a range of popular alloys should prove to be of interest.

Develops a linear programming model for integrated production planning based on the practice of a major Canadian steel making company. Considers the entire planning activity in the company as an integrated process involving a number of closely related sub‐functions, such as raw material purchasing, semi‐finished product purchasing and production, and capacity allocation, as well as finished product production and distribution. The mathematical programming model takes into account production costs, product throughput rates, customer demands, sales prices and facility capacities for optimal production planning. Presents a numerical example based on realistic system structure and practical planning data to illustrate the model. Computation results and analysis show that the integrated methodology is a feasible and practical approach for steel production planning.

The purpose of this study is to identify, analyse and model the post-processing barriers of 3D-printed medical models (3DPMM) printed by fused deposition modelling to overcome these barriers for improved operational efficiency in the Indian context.

The methodology used interpretive structural modelling (ISM), cross-impact matrix multiplication applied to classification (MICMAC) analysis and decision-making trial and evaluation laboratory (DEMATEL) to understand the hierarchical and contextual relations among the barriers of the post-processing.

A total of 11 post-processing barriers were identified in this study using ISM, literature review and experts’ input. The MICMAC analysis identified support material removal, surface finishing, cleaning, inspection and issues with quality consistency as significant driving barriers for post-processing. MICMAC also identified linkage barriers as well as dependent barriers. The ISM digraph model was developed using a final reachability matrix, which would help practitioners specifically tackle post-processing barriers. Further, the DEMATEL method allows practitioners to emphasize the causal effects of post-processing barriers and guides them in overcoming these barriers.

There may have been a few post-processing barriers that were overlooked by the Indian experts, which might have been important for other country’s perspective.

The presented ISM model and DEMATEL provide directions for operation managers in planning operational strategies for overcoming post-processing issues in the medical 3D-printing industry. Also, managers may formulate operational strategies based on the driving and dependence power of post-processing barriers as well as the causal effects relationships of the barriers.

This study contributes to identifying, analyzing and modelling the post-processing barriers of 3DPMM through a combined ISM and DEMATEL methodology, which has not yet been reviewed. This study also contributes to decision makers developing suitable strategies to overcome the post-processing barriers for improved operational efficiency.

Wood is one of the materials that is used for building construction either as structural member or as finishes from ages past to contemporary generation. It is composed of elongated, hollow spindle shaped cells that are arranged parallel to each other along the trunk of a tree. The resistance to water, chemicals, strength properties, appearance and decay rate is dictated by the fibrous cells. The purpose of this paper was to examine the application and use of wooden floor finish (an extract from wood) in residential buildings in Lagos, Nigeria, with a view to determine its effectiveness.

The study adopted a dual stage survey approach before the administration of questionnaire on 100 respondents that were selected through purposive sampling after the initial inquiry on the use of the material from 384 randomly selected samples from the entire population.

The study shows that the material is applied in all interior spaces except bathrooms and toilets. Minimal adoption is also seen in the kitchen area. Users indicate that wooden floor finish requires little maintenance, has low impact on users' health, considered safe-minimal occurrence of home accidents is recorded, has moderate thermal insulation and affordable.

The usage has impact on the environment due to continuous lumbering activities and lack of adequate plan for reforestation. This suggests that its sustainability depends on afforestation programmes. Its poor performance in sound insulation, water and fire resistance requires further attention. The maintenance is relatively easy and affordable.

The author made a new foray into investigating the performance of wooden floor finish due to its resurgence in the area bearing in mind the unseasoned condition of wood in circulation in the area. Previous adoptions were done by a less aggressive generation of well-trained artisans. Best places for its usage within the interior spaces are identified.

The purpose of this paper is to investigate the combination of selective laser melting (SLM) and 5-axis CNC milling to produce parts from titanium powder. The aim is to achieve a more resource-efficient manufacturing process by reducing material wastage and machining time, while adhering to quality requirements.

A benchmark titanium aerospace component is manufactured with two different approaches using subtractive and additive manufacturing technologies. The first component is produced from a solid billet using only 5-axis CNC milling. The second component is grown from powder using SLM to produce a net-shaped part of which the final shape and part accuracy are achieved through 5-axis CNC milling. The potential saving of material and machining time of the process combination is evaluated by comparing it to the conventional purely CNC approach. The form accuracy, surface finish, mechanical properties and tool wear for the two processes are also compared.

The results show that the process combination can be used to produce Ti components that adhere to aerospace standards. With the process combination, a material saving of 87 per cent was achieved along with a reduction of 21 per cent in machining time. Further improvements are possible using optimized SLM build and machining strategies.

This paper presents the results of a resource efficiency assessment on the combination of SLM and 5-axis CNC milling for the titanium alloy, Ti6Al4V. It is expected that this process combination can make a significant contribution towards reducing material wastage and machining time for aerospace applications.

It is a well-known fact that global warming is the extraordinary threat facing the world. The main reasons of these are human activities. Human beings have been contributing to the global warming in different ways for many years. Right material and product selection are some of the most important factors in the process of eliminating the negative effects of constructions on the natural environment and users. The life cycle of building materials involves the processes in which the products are extracted from the source. These processes are the stages of production, transportation, construction, use, demolition and destruction. Making wrong decisions in the selection and use of building materials may cause negative effects in the environment. The major purpose of this study is to to examine the embodied energy of of the traditional and comtemporary building materials according to the characteristics of the local climate. It will answer the question of; “What the embodied energy of a house was in the past and now” in Northern Cyprus. It will help to find out building materials with low embodied energy. There is no published database prepared for or in Northern Cyprus. In order to measure and evaluate the embodied energy of buildings and construction products in the world, there are no integrated systems in the Northern Cyprus at this point, while different countries have unique systems depending on the environmental, economic and social conditions of those countries. Measuring and controlling the environmental performance of environmental development is essential for the sustainable development of the Northern Cyprus.

By using the The Inventory of Carbon & Energy (ICE) program the embodied carbon statuses, embodied energy and transport energy and manufacture energy were discussed for each building material. As a result of this research it was found that locally produced or locally existing materials do not always give the best result in terms of embodied energy all the time. The energy consumption of building materials used in buildings and their associated carbon emissions will assist in the selection of environmentally friendly materials.