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This paper aims to develop a deep characterization of PA‐Al₂O₃ composite for selective laser sintering (SLS). Tension test is used to determine main mechanical characteristics of the material, both at room temperature and at 100°C. An accurate knowledge of the parts' performances as a function of the building orientation, is fundamental to understand the manufacturing anisotropy. Particular attention is dedicated to the joining and failure micromechanisms ruling the macroscopic characteristics, on the basis of the knowledge developed by the authors on SLS of both metal and polymeric powders.

Specimens have been built with different orientations in regard to powder deposition plane and laser path. Tension test is used to determine main mechanical characteristics of the material, both at room temperature and at 100°C. A particular attention is dedicated to the joining and failure micromechanisms ruling the macroscopic characteristics of the composite material by means of optical and scanning electron microscope (SEM) observations.

The sintered material shows an evident anisotropy in the growth direction (z‐axis), as well as it seems to be not sensitive to the sintering direction at room temperature (x, y, xy). At 100°C the effect of sintering direction becomes more evident and a different behaviour results considering x‐ and y‐direction, respectively. Accurate SEM characterization has been carried out to understand the effect of the manufacturing anisotropy on the mechanical performances, both in terms of additive construction and laser sintering strategy. The observation of the rupture surfaces showed that cracks originate from the external surface and propagate initially by the ductile failure of the polymeric matrix, up to the sudden fracture of the whole section.

Previous studies concerning polyamide charged parts confirm the importance of fabrication parameters and geometry on the final performances, due to anisotropic heat supply and transfer phenomena. The originality of the paper is in the investigation on both at room temperature and at 100°C. Moreover, a model is proposed where it is hypothesized that the layer‐by‐layer construction is only marginally responsible of the anisotropic behaviour of the material.

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 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.

Recent developments in additive manufacturing (AM) technology have emphasized the issue of social impacts. However, such effects are still to be determined. So, the purpose of this paper is to map the social impacts of AM technology.

The methodological approach applied in this study combines a literature review with computer-aided content analysis to search for keywords related to social impacts. The content analysis technique was used to identify and count the relevant keywords in academic documents associated with AM social impacts.

The study found that AM technology social impacts are still in an exploratory phase. Evidence was found that several social challenges of AM technology will have an influence on the society. The topics associated with fabrication, customization, sustainability, business models and work emerged as the most relevant terms that can act as “pointers” to social impacts.

The research on this subject is strongly conditioned by the scarcity of empirical experience and, consequently, by the scarcity of data and publications on the topic.

This study gives an up-to-date contribution to the topic of AM social impacts, which is still little explored in the literature. Moreover, the methodological approach used in this work combines bibliometrics with computer-aided content analysis, which also constitutes a contribution to support future literature reviews in any field. Overall, the results can be used to improve academic research in the topic and promote discussion among the different social actors.

The purpose of this paper is to present a custom-built tribometer that mimics the wear of additive manufactured fixtures used in inspection of sheet metal components.

Referring to the inspection of sheet metal parts, the fixture undergoes sliding wear during loading and unloading phases of the quality control operation. A new wear test is proposed to mimic the actual wearing conditions of the fixtures because the standards are deemed insufficient. In the tribometer, a cylindrical Alumide cantilever beam is made to slide back and forth inside a slightly bigger hole cut into a nickel-plated steel sheet. The sheet is spring loaded such that it applies a force on the specimen. The wear on the beam is measured after every 500 cycles of the beam motion.

Results of some first test trials are reported to evaluate the durability of Alumide fixtures fabricated by selective laser sintering. The results are also compared to those obtained for a machined fixture made of an Al-Cu alloy.

The proposed wear test estimates the life time of additive manufactured fixtures in terms of numbers of inspected components. The test can be extended to different materials to compare their durability.

Today, the fabrication of custom fixtures by means of additive manufacturing technologies is a reality in many manufacturing industries. The advantage of using those production technologies for custom fixtures is well assessed in literature in terms of manufacturing times and costs, whereas little attention was given to the life time and wear behaviour of fabricated fixtures. For its practical implication, the fixture durability is indeed very important for manufactures.

The purpose of this paper is to establish a methodology for the design and development of patient-specific elbow implant with an elastic modulus close to that of the human bone. One of the most preferred implant material is titanium alloy which is about 8 to 9 times higher in strength than that of the human bone and is the closest than other metallic biomedical materials.

The methodology begins with the design of the implant from patient-specific computed tomography information and incorporates the manufacturing of the implant via a novel rapid prototyping assisted microwave sintering process.

The elastic modulus and the flexural strength of the implant were observed to be comparable to that of human elbow bones. The fatigue test depicts that the implant survives the one million cycles under physiological loading conditions. Other mechanical properties such as impact energy absorption, hardness and life cycle tests were also evaluated. The implant surface promotes human cell growth and adhesion and does not cause any adverse or undesired effects i.e. no cytotoxicity.

Stress shielding, and therefore, aseptic loosening of the implant shall be avoided. In the event of any trauma post-implantation, the implant would not hurt the patient.

The present study describes a methodology for the first time to be able to obtain the strength required for the medical implant without sacrificing the fatigue life requirement.

The Mechanical Engineering course at the University of Campinas is composed of different disciplines in the areas of materials, mechanical design, manufacturing (production and manufacturing), computational systems, thermal and fluids. In the manufacturing area, in particular, there is a discipline entitled Productive Systems whose main objective is to offer to the student a global vision about operations management. In the field of operations management, sustainability is gaining more and more importance; thus, it is important to develop in the students a critical sense about social and environmental aspects. Thus, this paper aims to present the main initiatives developed in the discipline to promote sustainability in engineering students.

Since 2015, the professors responsible for the Productive Systems discipline, assisted by post-graduate students and professors from other universities, have begun to redesign the discipline, including debates, lectures, projects and other initiatives to provide a critical view concerning the traditional concepts taught. The discipline has been performed three times with this new conception. The methodology to structure this research was literature review, documental analyses of the discipline records and meetings with professors that participated in the initiatives. An Action Research approach was performed by two professors and a graduate student. The authors of this paper also compared the results with those obtained by initiatives performed at Chalmers University of Technology (Sweden).

This study allowed to reinforce some results from initiatives performed at Chalmers University of Technology (Sweden); however, some differences were identified. For example, similar to the initiatives mentioned, the professors of University of Campinas had problems with didactic books, as they loosely integrate the basic operations management concepts with sustainable development fundamentals. On the other hand, debates related to social sustainability were considered positive from the point of view of the professors and students, differing from initiatives performed at Chalmers University of Technology.

Results come from one field study (University of Campinas) when professors of the Mechanical Engineering course try to integrate operations management concepts and sustainable development. Different results may be observed by other higher education institutions.

The authors of this paper believe that the diffusion of these initiatives can stimulate other professors and researchers in the field to broaden the academic debate about the insertion of sustainability into engineering courses.

There are few papers presenting didactic experiences and empirical results about the integration of operations management concepts and sustainable development. Results of this paper reinforce some good practices and they also present other ones, in a way that extend the debate about educational engineering.

The purpose of this paper is to verify the feasibility and evaluate the dimensional accuracy of two rapid casting (RC) solutions based on 3D printing technology: investment casting starting from 3D‐printed starch patterns and the ZCast process for the production of cavities for light‐alloys castings.

Starting from the identification and design of a benchmark, technological prototypes were produced with the two RC processes. Measurements on a coordinate measuring machine allowed calculating the dimensional tolerances of the proposed technological chains. The predictive performances of computer aided engineering (CAE) software were verified when applied to the ZCast process modelling.

The research proved that both the investigated RC solutions are effective in obtaining cast technological prototypes in short times and with low costs, with dimensional tolerances that are completely consistent with metal casting processes.

The research assessed the feasibility and dimensional performances of two RC solutions, providing data that are extremely useful for the industrial application of the considered technologies.

The paper deals with experimental work on innovative techniques on which data are still lacking in literature. In particular, an original contribution to the determination of dimensional tolerances and the investigation on the predictive performances of commercial CAE software is provided.

The purpose of this paper is to evaluate how the direct access to additive manufacturing (AM) systems impacts on education of future mechanical engineers, within a Master’s program at a top Italian University.

A survey is specifically designed to assess the relevance of entry-level AM within the learning environment, as a tool for project development. The survey is distributed anonymously to three consecutive cohorts of students who attended the course of “computer-aided production (CAP)”, within the Master of Science Degree in Mechanical Engineering at Politecnico di Torino. The course includes a practical project, consisting in the design of a polymeric product with multiple components and ending with the production of an assembled prototype. The working assembly is fabricated by the students themselves, who operate a fused deposition modelling (FDM) machine, finish the parts and evaluate assemblability and functionality. The post-course survey covers diverse aspects of the learning process, such as: motivation, knowledge acquisition, new abilities and team-working skills. Responses are analyzed to evaluate students’ perception of the usefulness of additive technologies in learning product design and development. Among the projects, one representative case study is selected and discussed.

Results of the research affirm a positive relationship of access to AM devices to perceived interest, motivation and ease of learning of mechanical engineering. Entry-level additive technologies offer a hands-on experience within academia, fostering the acquisition of technical knowledge.

The survey is distributed to more than 200 students to cover the full population of the CAP course over three academic years. The year the students participated in the CAP course is not tracked because the instructor was the same and there were no administrative differences. For this reason, the survey administration might be a limitation of the current study. In addition to this, no gender distinction is made because historically, the percentage of female students in Mechanical Engineering courses is about 10 per cent or lower. Although the answers to the survey are anonymous, only 37 per cent of the students gave a feedback. Thus, on the one hand, impact assessment is limited to a sample of about one-third of the complete population, but, on the other hand, the anonymity ensures randomization in the sample selection.

Early exposure of forthcoming designers to AM tools can turn into a “think-additive” approach to product design, that is a groundbreaking conception of geometries and product functionalities, leading to the full exploitation of the possibilities offered by additive technologies.

Shared knowledge can act as a springboard for mass adoption of AM processes.

The advantages of adopting AM technologies at different levels of education, for diverse educational purposes and disciplines, are well assessed in the literature. The innovative aspect of this paper is that the impact of AM is evaluated through a feedback coming directly from mechanical engineering students.

Manufacturing of products loaded with torque in an incremental process should take into account the strength in relation to the internal structure of the details. Incremental processes allow for obtaining various internal structures, both in the production process itself and as a result of designing a three-dimensional computer-aided design model with programmable strength. Finite element analysis (FEA) is often used in the modeling process, especially in the area of topological optimization. There is a lack of data for numerical simulation processes, especially for the design of products loaded with torque and manufactured additive manufacturing (AM). The purpose of this study is to present the influence of the internal structure of samples produced in the material extrusion (MEX) technology on the tested parameters in the process of unidirectional torsion and to present the practical application of the obtained results on the example of a spline connection.

The work involved a process of unidirectional torsion of samples with different internal structures, produced in the MEX technology. The obtained results allowed for the FEA of the spline connection, which was compared with the test of unidirectional torsion of the connection.

The performance of the unidirectional torsion test and the obtained results allowed us to determine the influence of the internal structure and its density on the achieved values of the tested parameters of the analyzed prototype materials. The performed FEA of the spline connection reflects the deformation of the produced connection in the unidirectional torsion test.

There are no standards for the torsional strength of elements manufactured from polymeric materials using MEX methods, which is why the industry often does not use these methods due to the need to spend time on research, which is associated with high costs. In addition, the industry is vary of unknown solutions and limits their use. Therefore, it is important to determine, among others, the strength parameters of components manufactured using incremental methods, including MEX, so that they can be widely used because of their great potential and thus gain trust among the recipient market. In addition, taking into account the different densities of the applied filling structure of the samples made of six prototype materials commonly available from manufacturers allowed us to determine its effect on the torsional strength. The presented work can be the basis for constructors dealing with the design of elements manufactured in the MEX technology in terms of torsional strength. The obtained results also complement the existing material base in the FEA software and perform the strength analysis before the actual details are made to verify the existing irregularities that affect the strength of the details. The analysis of unidirectional torsion made it possible to supplement the material cards, which often refer to unprocessed material, e.g. in MEX processes.