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Over the past few years, the number of related research to additive manufacturing (AM) has risen. The selective composite formation (SCF) can also be found among the new technologies that were developed. This technology was first introduced in 2013, and because of its innovative character, there are still many challenges to be overcome. Therefore, the main aim of this study is to present a finite element method which allows to investigate the processing of the material during the selective formation of a composite material based on cellulose and acrylic.

In the beginning, we introduced a brand new finite element method approach which is based on light transmittance network and photopolymerisation in transient state. This method is mainly characterised by internal light absorption, transversal reflectance, light transmittance coefficient and photopolymerisation kinetics. The authors defined experimentally the main model coefficients besides investigating the formation of composite material in six case studies. The main variables evaluated in those studies were the number of layers and the number of lines. By the end, the degree of polymer conversion and the preliminary evaluation of adherence between layers were identified in addition to the formation profile of composite material.

The presented method evidence that the SCF resulted in a profile of polymerisation which is different from profiles found in vat polymerisation processes. It was shown that the light diffraction increases polymerisation area to outside of laser limits and reduces the penetration depth. It was also exposed that the selective formation of composite material on the top layer interferes with the polymerisation of previous layers and might increase the polymerised area in about 25 per cent per layer. By the end, adherence between layers was evidenced because of a high-pass filter that limited polymer conversion to over 60 per cent. In this case, the adherence between the top layers was provided by the interface between layers, while the deeper layers resulted in a solid formed by composite.

This paper presents research results related to a very new AM technology and also proposes a new method to characterise this concept. Because of this new analytic approach, the process planning can be simulated and optimised, in addition to being a useful tool for other researches related to photocurable polymers and AM technologies.

This paper aims to argue about the involvement of additive technologies (ATs) in the prototyping issues of designing. More precisely, it reviews the literature contributions focused on the different perspectives of prototyping activities for design purposes, searching for both available knowledge and research needs concerning the correct exploitation of ATs.

A two-step literature review has been performed. In the first step, general information has been retrieved about prototyping issues related to design. In the second step, the literature searches were focused on retrieving more detailed information about ATs, concerning each of the main issues identified in the previous step. Extracted information has been analyzed and discussed for understanding the actual coverage of the arguments and for identifying possible research needs.

Four generally valid prototyping issues have been identified in the first step of the literature review. For each of them, available information and current lacks have been identified and discussed about the involvement of AT, allowing to extract six different research hints for future works.

This is the first literature review concerning AT-focused contributions that cover the complex and inter-disciplinary issues characterizing prototyping activities in design contexts.

The purpose of this paper is to introduce coherent Industry 4.0 definition via a rigorous analysis framework, and provide a holistic view of technological, organizational and other key aspects (variables) of Industry 4.0 along with the identification of interdependencies that co-occur between them.

The study conducts a systematic literature review using Preferred Reporting Items for Systematic Review and Meta-Analysis methodology, and includes 675 papers analyzed both quantitatively and qualitatively. The former utilizes TIBCO Statistica. Furthermore, to define Industry 4.0, the authors reviewed 52 publications.

Industry 4.0 is a multidimensional system of value creation that includes 42 groups of terms in management, organizational and business-related variables, 30 technological and manufacturing-related variables – classified into seven categories – and several interdependencies that co-occur between them.

The analyses’ outcomes are of high importance both for academia and industry practitioners, as the findings elucidate the meaning of Industry 4.0 and may be used as the basis of future research in management, production management, industrial organizations and other Industry 4.0-related disciplines. Regarding industrial companies, the publication serves as a compendium, and should support industrial businesses in the transition from traditional manufacturing into the Industry 4.0 era.

This work’s novelty and value is threefold: first, the paper introduces an Industry 4.0 definition framework based on the most popular publications in the field. Second, the paper identifies and presents Industry 4.0’s common technologies and organizational variables via a systematic and current literature review. Finally, the paper extends the ongoing discourse on Industry 4.0. For the first time in this discipline, interdependences between identified Industry 4.0 variables are presented and discussed.

Additively manufactured objects have layered structures, which means post processing is often required to achieve a desired surface finish. Furthermore, the additive nature of the process makes it less accurate than subtractive processes. Hence, additive manufacturing techniques could tremendously benefit from finishing processes to improve their geometric tolerance and surface finish.

Rotary ultrasonic machining (RUM) was chosen as a finishing operation for drilling additively manufactured carbon fiber reinforced polymer (CFRP) composites. Two distinct additive manufacturing methods of fused deposition modeling (FDM) and laser-assisted laminated object manufacturing (LA-LOM) were used to fabricate CFRP plates with continuous carbon fiber reinforcement. The influence of the feedrate, tool rotation speed and ultrasonic power of the RUM process parameters on the aforementioned quality characteristics revealed the feasibility of RUM process as a finishing operation for additive manufactured CFRP.

The quality of drilled holes in the CFRP plates fabricated via LA-LOM was supremely superior to the FDM counterparts with less pullout delamination, smoother surface and less burr formation. The strong interfacial bonding in LA-LOM proven to be superior to FDM was able to endure higher cutting force of the RUM process. The cutting force and cutting temperature overwhelmed the FDM parts and induced higher surface damage.

Overall, the present study demonstrates the feasibility of a hybrid additive and subtractive manufacturing method that could potentially reduce cost and waste of the CFRP production for industrial applications.

In this study, the authors explore how novel and relevant technologies can change the overall design of systems, and which factors influence the design of resilient systems in particular. After evaluating the effects of these factors, the authors describe the potential role of AM-supported maintenance operations in military logistics and draw broader conclusions regarding designing for resilience.

The authors build a simulation model of the AM-supported maintenance capability of a mechanised battalion to analyse factors affecting its resilience. AM production capacity specifically refers to metal printing and was verified by data generated from 3D printing of the actual APC parts.

The current AM speed is not able to increase resilience at the depot level, so at present, increasing the spare parts inventory is a better way to improve resilience. However, with future improvements in speed the AM may become feasible in battlefield maintenance.

AM holds great promise in increasing resilience of especially the spare part logistics. At present technology, it is not yet fully realised in the case.

The authors suggest a concrete system performance measure, where reaching a concrete limit, system resilience is lost. The authors present arguments for a definition of resilience where pre-disruption activities are not part of resilience. The authors maintain that simulation, with its ability to include detail, is well-suited in design-for-resilience because supply chains are context dependent and disruptions unexpected.

The purpose of this paper is to discover how Hungarian manufacturing companies interpret technology and human resources as driving forces and barriers in terms of Industry 4.0 implementation.

The authors conducted 23 semi-structured interviews with corporate leaders and applied qualitative content analysis using Atlas.ti software.

The authors formulated a new definition of Industry 4.0 which emphasises the role of human factors. The authors identified driving forces (efficiency with speed/information flow/precision) and barriers (technology compatibility, human fears and lack of digital skills) in terms of Industry 4.0 implementation and developed the DIGI-TEcH performance management dimensions.

Comparison with other countries is limited. Given the exploratory and qualitative nature, further quantitative research would be needed to generalise results. Finally, only manufacturing companies are examined.

It provides empirical evidence to practitioners to understand concerns about technology and human resource in terms of Industry 4.0 implementation. In addition, corporate performance management can be extended by the developed DIGI-TEcH dimensions.

This paper reveals key evidence for the uptake of technology and human factors in terms of Industry 4.0 implementation and their impacts on corporate operation and performance. It also provides an insight into a specific country context, which can be a useful benchmark for other Central and Eastern European countries.

The purpose of this paper is to investigate the fundamentals of the selective inhibition sintering (SIS) process for fabricating dense metallic parts.

A SIS‐Metal process based on the microscopic mechanical inhibition is developed. In the process, salt solution is printed in the selected area of each powder layer; the salt re‐crystallizes when water evaporates; salt crystals decompose and grow rapidly prior to sintering; the generated salt particles spread between metal powder particles and prevent the fusing of these particles together, hence inhibiting the sintering process in the affected regions.

The SIS‐Metal process has numerous advantages. An inhibition of sintering mechanism is established for the future development of the technology. Through chemical and visual analysis using STM the mechanism for the inhibition phenomenon has been identified.

Only bronze powder has been used in the research. Accordingly, the inhibition chemical has been engineered for this material choice. The approach should be feasible for other metals but a proper inhibitor would need to be found for each material choice.

The only limitation envisioned for the process may be the removal after sintering of inhibited sections in hard‐to reach areas using physical means such as scraping or vibration. Chemical removal of such sections should be possible, however.

The paper illustrates a new additive manufacturing technology for metallic parts fabrication.

This paper aims to provide a review of four-dimensional (4D) printing of shape memory polymers using inkjet printing technology. 4D printing refers to the three-dimensional (3D) printing of smart materials capable of shape change or function modification with respect to time when activated by external stimuli. Inkjet printing has gained popularity because of the technical advantages such as non-contact deposition, multi-material printing, high resolution, high speed of printing and minimal post processing. This review will serve as a platform for understanding the inkjet 4D printing process and the shape memory capability of the polymer structures printed using inkjet printing.

The approach used in this review was to search for and review research works related to inkjet 4D printing of shape memory polymers. The search period was limited for the duration 2013 to 2021 as the 4D printing technology came into light later in 2013. With the review of inkjet 4D printing of shape memory polymers, the shape memory capability of the inkjet-printed structures were also studied.

With the available research documents, it was found that the inkjet 4D printing technology gained momentum from 2016, three years after the introduction of the 4D printing technology. The key findings of this review show that inkjet 4D printing of shape memory polymers were primarily performed using commercial inkjet printers and polymer inks linked to the printers. Even though the inkjet printing technology is matured enough to print multiple materials, development of shape memory polymer inks for inkjet printability remains complex. To realize the full potential of inkjet 4D printing, novel polymer inks specific for inkjet printing needs development.

The major limitation to this review was the availability of research papers for review. Even though inkjet printing technology has grown to popularity in the graphics printing and publishing industry since its inception in the 19th century, the technology still needs to evolve in the printing of 3D structures due to the limitations in synthesizing inks that are inkjet printable. However, this research will serve as a platform for understating the current status of inkjet 4D printing and the limitations of the technology.

This review focuses only on the inkjet 4D printing of shape memory polymers among the generally summarized 4D printing review papers available. Currently, 4D printing of shape memory polymers is carried out using only the commercially available polymer printers. Also, researchers do not have the flexibility of modifying the polymer inks linked to the printers. This review can spur more research into the development of novel polymer inks specific for inkjet printing.