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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 present a hierarchical multiscale model to evaluate the effect of fused deposition modeling (FDM) process parameters on mechanical properties. Asymptotic homogenization mathematical theory is developed into two scales (micro and macro scales) to compute the effective elastic and shear modulus of the printed parts. Four parameters, namely, raster orientation, layer height, build orientation and porosity are studied.

The representative volume elements (RVEs) are generated by mimicking the microstructure of the printed parts. The RVEs subjected to periodic boundary conditions were solved using finite element. The experimental characterization according to ASTM D638 was conducted to validate the computational modeling results.

The computational model reports reduction (E1, ∼>38%) and (G12, ∼>50%) when porosity increased. The elastic modulus increases (1.31%–47.68%) increasing the orthotropic behavior in parts. Quasi-solids parts (100% infill) possess 10.71% voids. A reduction of 11.5% and 16.5% in elastic modulus with layer height is reported. In total, 45–450 oriented parts were highly orthotropic, and 0–00 parts were strongest. The order of parameters affecting the mechanical properties is porosity > layer height > raster orientation > build orientation.

This study adds value to the state-of-the-art terms of construction of RVEs using slicing software, discarding the necessity of image processing and study of porosity in FDM parts, reporting that the infill density is not the only measure of porosity in these parts.

The purpose of this paper is to improve the automation of selective disassembly sequence planning (SDSP) and generate the optimal or near-optimal disassembly sequences.

The disassembly constraints is automatically extracted from the computer-aided design (CAD) model of products and represented as disassembly constraint matrices for DSP. A new disassembly planning model is built for computing the optimal disassembly sequences. The immune algorithm (IA) is improved for finding the optimal or near-optimal disassembly sequences.

The workload for recognizing disassembly constraints is avoided for DSP. The disassembly constraints are useful for generating feasible and optimal solutions. The improved IA has the better performance than the genetic algorithm, IA and particle swarm optimization for DSP.

All parts must have rigid bodies, flexible and soft parts are not considered. After the global coordinate system is given, every part is disassembled along one of the six disassembly directions –X, +X, –Y, +Y, –Z and +Z. All connections between the parts can be removed, and all parts can be disassembled.

The disassembly constraints are extracted from CAD model of products, which improves the automation of DSP. The disassembly model is useful for reducing the computation of generating the feasible and optimal disassembly sequences. The improved IA converges to the optimal disassembly sequence quickly.

The purpose of this paper is to identify the main reasons for spare parts logistics failures and address logistics distribution design in order to achieve the desired level of after-sales maintenance service.

This research is based on an empirical case study on a large corporation providing worldwide with retail banking hardware, software and services. The case study focuses on the automated teller machine (ATM) part of activities, with a focus on the spare parts distribution and after-sales service network in the Eastern Europe.

The proposed network solution of multiple distribution centers with short-cut distance saving approach will enable the case study company to redesign their spare part logistics architecture in order to achieve short response time. Research findings reveal possible spare parts delivery delays and thus the service-level agreement failures with clients in the case study company.

This research covers a particular supply chain environment and identified research gaps. It discusses a time-based responsive logistics problem and develops a conceptual framework that would help researchers to better understand logistics challenges of installed equipment maintenance and after-sales service.

This case study research shows the “big picture” of spare parts logistics challenges as vital part of installed equipment after-sales and maintenance service network, as well as emphasizes how the unique context of a market like Russian Federation can set-up a distribution network efficiently. Strategies applied to handle such service-level failures, reverse logistics aspects of repairable and non-repairable spare parts to such large ATM after-sales service network based on this longitudinal case offer value for similar scale companies.

Understanding how material jetting process parameters affect material properties can inform design and print orientation when manufacturing end-use components. This study aims to explore the robustness of material properties in material jetted components to variations in processing environment and build orientation.

The authors characterized the properties of six different material gradients produced from preset “digital material” mixes of polypropylene-like (VeroWhitePlus) and elastomer-like (TangoBlackPlus) materials. Tensile stress, modulus of elasticity and elongation at break were analyzed for each material printed at three different build orientations. In a separate ten-week study, the authors investigated the effects of aging in different lighting conditions on material properties.

Specimens fabricated with their longest dimension along the direction of the print head travel (X-axis) tended to have the largest tensile strength, but trends in elastic modulus and elongation at break varied between the rigid and flexible photopolymers. The aging study showed that the ultimate tensile stress of VeroWhitePlus parts increased and the elongation decreased over time. Material properties were not significantly altered by lighting conditions.

Many tensile specimens failed at the neck region, especially for the more elastomeric parts. It is hypothesized that this is due to the material jetting process approximating curves with a pixelated droplet arrangement, instead of curved contour as seen in other additive manufacturing processes. A new tensile specimen design that performs more consistently with elastomer-like materials should be considered. The aging component of this study is focused solely on polypropylene-like (VeroWhitePlus) material; additional research into the effects of aging on multiple composite materials is needed.

The study provides the first known description of orientation effects on the mechanical behavior of photopolymers containing varied concentrations of elastomeric (TangoBlackPlus) material. The aging study presents the first findings on how time affects parts made via material jetting.

The weapon system of The Navy is the small quantity producing system on multiple kinds. It is consisted of various equipment and the subordinate parts of those which can repair the damaged part. The operating procedure concerning warship's repair parts managed under these systems is as follows. Firstly, if demand of repair parts occurs from warship which is the operating unit of weapon, then the Fleet(the repair & supply support battalion) is in charge of dealing with these requests. If certain request from warship is beyond the battalion's capability, it is delivered directly to the Logistic Command. In short, the repair and supply support system of repair parts can be described as the multi-level support system. The various theoretical researches on inventory management of Navy's repair parts and simulation study that reflects reality in detail have been carried out simultaneously. However, the majority of existing research has been conducted on aircraft and tank's repairable items, in that, the studies is woefully deficient in the area concerning Navy's inventory management. For that reason, this paper firstly constructs the model of consumable items that is frequently damaged reflecting characteristics of navy's repair parts inventory management using ARENA simulation. After that, this paper is trying to propose methodology to analyze optimal inventory level of each supply unit through OptQuest, the optimization program of ARENA simulation.

Despite the proven benefits of high‐performing spare parts logistics, recommendations on how to organize spare parts logistics in China are rather rare. The absence of spare parts logistics concepts for China is surprising, since the spare part business is the profit pool of the capital goods industry: spare parts create about 17 percent of the industry's total revenue. The margins involved in this spare parts revenue are, on average, 25 percent compared to 2‐3 percent of the capital goods. This paper aims to offer recommendations to increase spare parts logistics performance.

The authors conducted an extensive benchmarking project with a variety of firms (focus group and single case study) in order to gain a better understanding of spare parts logistics in China. By reviewing the first benchmarking findings with a single company that struggled to achieve sufficient spare parts logistics performance, additional insight was gained into how spare parts logistics should be organized in China.

The paper attempts to provide a better understanding of the necessary changes for improving logistics performance in the Chinese market. It analyzes the necessary changes to achieve a cutting‐edge logistics solution, and shows how companies can implement the solution.

Research limitations come from the qualitative nature of the research.

Managers can use the results obtained in this study to challenge their current logistics practices and develop a project procedure on how to initiate logistics projects that lead to cutting‐edge logistics performance.

Rather than concentrating on performance benchmarks of the supply chain of spare parts or specific aspects of spare parts management, the paper develops the setting up of a cutting‐edge logistics solution for China and Asia. The cutting‐edge solution is based on two main pillars: companies should try to develop logistics solutions for Asia that consider existing Asian and Chinese constraints instead of taking the logistics practices used in mature markets and trying to adapt them to the Chinese market, and the development of the logistics solution should be in intensive collaboration with the logistics providers.

Organisations either keep spares for their own use, or‐for‐sale to other organisations. In either case, the ultimate need is to be able to replace worn or defective parts in operational machinery or equipment. In an economic sense, spares are kept to meet the needs of the situation in the cheapest way.

A study was conducted on a leading US‐based computer maker to examine its reverse logistics operations in the Asia‐Pacific region. This US company had set up a spare parts business unit in Singapore to take care of the Asia‐Pacific customers for its products, which were still under warranty or service contracts. Defective parts were sent to its US headquarters for refurbishment and repair, and subsequently return to the Asia‐Pacific region. The study revealed a number of interesting findings. These included: about 50 percent of the products returned to the USA cost less than half the reverse logistics costs; the current information technology systems supporting the reverse logistics operations are not used in assisting the company’s managers in making critical decisions but in data collection; and decision making on reverse logistics at each of the company’s Asia‐Pacific offices was inconsistent and lacked standardization. Recommendations were subsequently made to overcome some of the inefficiencies in managing the reverse supply chain.

Scheduled building maintenance requires appropriate and adequate spare parts to replace existing parts on a regular basis. Management of spare parts is seen as an important criterion to ensure the efficiency of scheduled maintenance. The purpose of this paper is to identify the contributors of spare parts management and investigate the relationship between these contributors and maintenance cost performance.

This research adopted a quantitative approach, which utilised questionnaire surveys to study the relationship between the contributors of spare parts management and maintenance cost performance. The data were analysed through descriptive analysis, correlation, and regression analysis. Additionally, a case study was examined to validate the results obtained from the survey.

The results of this research demonstrated that the quality of spare parts (QSP), budget allocation for acquisition of spare parts, and level of stocks were significantly correlated to the maintenance cost variance (MCV). Moreover, the results of the regression analysis indicated that the QSP was the significant predictor of MCV.

This research highlights the importance of spare parts management in building maintenance. It recommends that maintenance management set up a spare parts management department for updating stocks frequently. Meanwhile, the management should avoid ad-hoc acquisition of spare parts, as this is always more expensive. The management should also select spare parts based on quality instead of lowest cost. In addition, building managers should also apply the developed regression model in practice to predict and improve maintenance performance.