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The purpose of present paper is to enlarge the knowledge about the performance of gypsum powder to realize complex molds or cores for aluminum casting.

The research was divided into two activities: simple; and complex-part production capability. In the simple-part step, the performance of gypsum powder and the minimum mold thickness that would withstand the casting process. In the complex-part step, the authors first investigated the powder removability as a function of geometry complexity and then binder jetting performance was evaluated for the case of lattice-structure fabrication.

All the geometries tested withstand the casting process demonstrating the benefits in terms of complexity part design; however, the process suffers of all the typical defect of casting as misrun, porosity and cold shut.

The results found in this research improve the benefits related to additive manufacturing application in industrial environment and in particular to the binder jetting technology and the rapid casting approach.

This paper aims to review the industrial and biomedical applications of state-of-the-art fused deposition modelling (FDM)-assisted investment casting (FDMAIC). Brief literature survey of methodologies, ideas, techniques and approaches used by various researchers is highlighted and use of hybrid feedstock filament-based pattern to produce metal matrix composite is duly discussed.

Pattern replica required for investment casting (IC) of biomedical implant, machine parts, dentistry and other industrial components can be directly produced by using FDM process is presented. Relevant studies and examples explaining the suitability of FDMAIC for various applications are also presented.

Researches to optimize the conventional IC with FDM solutions and develop new hybrid feedstock filament of FDM done by researchers worldwide are also discussed. The review highlights the benefit of FDMAIC to surgeons, engineers and manufacturing organizations.

The research related to this survey is limited to the suitability and applicability of FDMAIC.

This review presents the information regarding potential IC application, which facilitates the society, engineers and manufacturing organizations by providing variety of components for assisting FDM. The information reported in this paper will serve doctors, researchers, organizations and academicians to explore the new options in the field of FDMAIC.

Expanded polystyrene (EPS) is a low‐density and cheap material, which has been widely used in commercial areas. As the demand for small‐batch, flexible and quick production increases, producing EPS products with metals moulds has become unaffordable. The purpose of this paper is to describe the development of an EPS rapid prototyping (ERP) process, with an electric heating tool.

Two new cutting strategies for the ERP process, constant angle mode and constant thickness mode, are proposed. The methods to generate tool path of those models are also discussed. In order to improve accuracy and cutting effectiveness, experiments have been carried out to investigate the thermal characteristics in the ERP process. Consequently, the relationships between the size of material removal area and process parameters are obtained. Suitable processing parameters for the ERP system are also conducted.

It is found that the ERP process can rapidly produce complex three‐dimensional parts in one‐off clamping without post‐processing procedures as in traditional rapid prototyping, such as, extra support removing, step texture finishing and distortion regulating.

The paper provides several examples to explain and illustrate the applicability and workflow of the ERP system.

This paper seeks to review the industrial applications of state‐of‐the‐art additive manufacturing (AM) techniques in metal casting technology. An extensive survey of concepts, techniques, approaches and suitability of various commercialised rapid casting (RC) solutions with traditional casting methods is presented.

The tooling required for producing metal casting such as fabrication of patterns, cores and moulds with RC directly by using different approaches are presented and evaluated. Relevant case studies and examples explaining the suitability and problems of using RC solutions by various manufacturers and researchers are also presented.

Latest research to optimize the current RC solutions, and new inventions in processing techniques and materials in RC performed by researchers worldwide are also discussed. The discussion regarding the benefits of RC solutions to foundrymen, and challenges to produce accurate and cost‐effective RC amongst AM manufacturers concludes this paper.

The research related to this survey is limited to the applicability of RC solutions to sand casting and investment casting processes. There is practically no implication in industrial application of RC technology.

This review presents the information regarding potential AM application – RC, which facilitates the fabrication of patterns, cores and moulds directly using the computer‐aided design data. The information available in this paper serves the purpose of researchers and academicians to explore the new options in the field of RC and especially users, manufacturers and service industries to produce casting in relatively much shorter time and at low cost and even to cast complex design components which otherwise was impossible by using traditional casting processes and CNC technology.

The purpose of this paper is to analyze the current state of the art manufacturing techniques using sand molds for the casting industry by the means of additive manufacturing (AM). In particular, this review will cover two families of 3D printing in regards to sand mold fabrication.

This paper will discuss the sand casting manufacturing processes of AM by binder jetting (3D printing) and selective laser sintering. Scientific articles, patents and case studies are analyzed. Topics ranging from the technology types to the economic implications are covered.

The review investigates new factors and methods for mold design, looking at mechanical properties and cost analysis as influenced by material selection, thermal characteristics, topological optimization and manufacturing procedure. Findings in this study suggest that this topic lacks vigorous scientific research and that the case studies by manufacturers thus far are not useful.

As demonstrated by the limited data from previous published studies, a more comprehensive and conclusive analysis is needed due to the lack of interest and resources regarding the AM of sand molds.

This study is a useful tool for any researchers with an interest in the field of AM of sand molds.

Key perspectives are proposed.

This review highlights current gaps in this field. The review goes beyond the scientific articles by curating patents and professional case studies.

To develop a numerical methodology to simulate the lost foam casting (LFC), including the gas back‐pressure effects.

Back‐pressure effects are due to the interactions of many physical processes. The strategy proposed herein tries to model all these processes within a simple formula. The main characteristic of the model consists of assuming that the back‐pressure is a known function of the external parameters (coating, temperature, gravity, etc.) that affects directly the heat transfer coefficient from the metal to the foam. The general framework of the simulation is a finite element model based on an arbitrary Lagrangian Eulerian (ALE) approach and the use of level set function to capture the metal front advance.

After experimental tunings, the model provides a way to include the back‐pressure effects in a simple way.

The method is not completely predictive in the sense that a priori tuning is necessary to calibrate the model.

Provides more realistic results than classical models.

The paper proposes a theoretical framework of a finite element method for the simulation of LFC process. The method uses an ALE method on a fixed mesh and a level‐set function to capture metal front advance. It proposes an original formula for the heat transfer coefficient that enables one to include back‐pressure effects.

This case describes how eight entrepreneurs discover different opportunities for new businesses to exploit a single technological invention. The case focuses on the process of entrepreneurial discovery and its implications for the creation of new firms. Many of the teaching materials on entrepreneurship assume that entrepreneurs have already discovered an opportunity. While these materials provide useful information about the process of creating new enterprises, they miss the crucial first step in the entrepreneurial process: identifying an opportunity. The case illustrates the theoretical concept of the role of information in the discovery of entrepreneurial opportunities. It can be used in a class on entrepreneurship or management of technology.

At this stage I think that we can usefully give some detailed consideration to the copper‐aluminium alloys, and reference may in this connection be made to the equilibrium diagram shown in Fig. I, which, as in the case of the steels, gives an explanation of, and is a guide to, their behaviour and heat‐treatment.

Tracheobronchial stents are commonly used in airway management as a form of palliation for obstruction. This form of therapy immediately relieves the patients from life‐threatening conditions and significantly improves their quality of life. In the cases of complex tracheobronchial obstruction, customised airway stents are required for effective palliation. In this work, an Airway Stent Customisation Protocol (ASCP) is introduced.

It describes two variant routes that use a combination of rapid prototyping (RP) and rapid tooling (RT) techniques to fabricate customised airway stents in short lead times. The ASCP allows the stents to be tailored in terms of geometry, and distending strength. A brief comparison between the ASCP and other RP/RT manufacturing routes is also carried out.

The ability to customise airway stents in short lead times is important as it allows surgeons to swiftly treat life‐threatening conditions arising from tracheobronchial obstructions. It is shown that the ASCP is capable of providing relief to patients quickly. The application of RP and RT in the ASCP has not only allowed shorter response time to patients, but has also allowed the stents to be produced at a relatively low cost.

Tracheobronchial stents are commonly used in patients facing advanced stages of cancer. Focuses on a time and cost‐effective solution that is provided to improve their quality of life.

The purpose of this paper is to demonstrate the use of three‐dimensional printing (3DP) process as a base technology for rapid manufacturing of components, larger than the machine's build volume. This extends the 3DP applications field beyond its existing domain. The paper gives process chains and design for manufacturing and assembly guidelines.

Several parameters influencing the process chains are identified and their interrelations investigated. Based on this study, new process chains are developed for specific functional and material requirements. The new process chains are validated with several case studies. Where applicable, the process chains are compared qualitatively with existing methods.

The results show that the new process chains are as fast as or faster than existing methods and have similar accuracy. The most significant advantage is a more geometric freedom. There is also more opportunity for checking physical models before making the final part. Some limitations to the processes are identified and given as design guidelines.

A quantitative comparison of existing methods with the new process was not possible.

The study provides useful design for manufacturing guidelines.

This paper shows how 3DP technology, originally only conceived as a concept modeller, can be used to manufacture components that are larger than the rapid prototyping machine's build volume. It gives guidelines for designers wishing to follow a similar route.