Manufacturing Process Selection Research Articles

Multi-objective optimization for selecting sustainable materials with simultaneous consideration of several components in a product

ABSTRACT Today, in addition to economic issues, companies face social and environmental challenges in designing their products to stay in a competitive world. One of the essential steps in product sustainability is material selection. Determining the optimal combination of materials to make multi-component products is complicated because there are several material alternatives for each component. In this paper, an integer programming approach is proposed to select materials for products that are composed of many components. In this model, several issues are integrated and solved simultaneously: material selection, supplier selection, manufacturing process selection, assembly process selection, and end-of-life option determination. The objectives of this model are to minimise the producer’s cost and the environmental impact through the entire product life cycle. In order to validate the proposed model, a case study has been conducted in the automotive industry. Finally, by sensitivity analyses, weight reduction on cost and environmental impact has been investigated. The results indicate that lightweight materials are not always the best option in terms of environmental consideration.

A data-driven framework for learning the capability of manufacturing process sequences

Automatically acquiring knowledge of manufacturing process capabilities described in terms of the part shapes they can produce, materials they can process, and part qualities they can generate is necessary to enable on-demand cyber manufacturing. This paper aims to present a novel data-driven framework to (i) identify the sequences of processes used to manufacture a discrete part, and (ii) describe their capabilities via quantifiable descriptors of shape, material properties, and part quality. Specifically, given existing manufacturing data consisting of different parts and their corresponding manufacturing methods, the proposed framework utilizes a sequence mining algorithm to identify frequently occurring sequence patterns of different manufacturing processes. In addition, the manufacturing capability of each sequence pattern is described quantitatively in terms of the achievable shapes, material properties, and part quality metrics. Such manufacturing process capability descriptions can be queried to obtain suggestions of feasible process sequences with the capability to manufacture a new part design. An exemplar implementation of the proposed framework with a curated manufacturing dataset is given to illustrate how the framework can enable manufacturing process selection and planning. The high Confidence Rates achieved by the proposed framework show its predictive strength for use in Computer Aided Process Planning (CAPP).

Robust Metal Additive Manufacturing Process Selection and Development for Aerospace Components

Metal additive manufacturing (AM) encapsulates the myriad of manufacturing processes available to meet industrial needs. Determining which of these AM processes is best for a specific aerospace application can be overwhelming. Based on the application, each of these AM processes has advantages and challenges. The most common metal AM methods in use include Powder Bed Fusion, Directed Energy Deposition, and various solid-state processes. Within each of these processes, there are different energy sources and feedstock requirements. Component requirements heavily affect the process determination, despite existing literature on these AM processes (often inclusive of input parameters and material properties). This article provides an overview of the considerations taken for metal AM process selection for aerospace components based on various attributes. These attributes include geometric considerations, metallurgical characteristics and properties, cost basis, post-processing, and industrialization supply chain maturity. To provide information for trade studies and selection, data on these attributes were compiled through literature reviews, internal NASA studies, as well as academic and industry partner studies and data. These studies include multiple AM components and sample build experiments to evaluate (1) material and geometric variations and constraints within the processes, (2) alloy characterization and mechanical testing, (3) pathfinder component development and hot-fire evaluations, and (4) qualification approaches. This article summarizes these results and is meant to introduce various considerations when designing a metal AM component.

System model driven selection of robust tablet manufacturing processes based on drug loading and formulation physical attributes

Mechanistic process modeling presents an opportunity to reduce experimental burden, enabling relationships between process parameters and product attributes to be mapped out using in-silico experiments. A system model of a pharmaceutical tablet manufacturing process comparing dry granulation with direct compression is developed to answer key material and process design questions. The system model links API physical properties and formulation to process parameters to map out the robust operating space. To demonstrate the application of the model, several drug product formulation design questions were considered:•Which processing route is the most robust given the API material properties and dosage requirements?•How does drug loading and tablet size impact the robustness of the manufacturing process?•What process settings are required for a robust manufacturing route for the API material properties and drug loading requirements?A computational framework was developed using the system models to generate process classification and design space maps to aid robust pharmaceutical formulation and process decision making. Process classification maps were produced to assess the feasibility of roller compaction and direct compression for different material properties and formulations. Constraints on the critical quality attributes of the intermediate and final products were defined using the Manufacturing Classification System. Design space maps presented here demonstrate how system models can be used to support formulation and process design. The design space maps illustrate how the process operating space can be increased or decreased as the API mass fraction is varied.The process design and selection system model demonstrate how an understanding of the API physical properties can be used to model the impact of formulation and process design. Furthermore, these models can be instrumental in the dialogue with colleagues developing the API in order to set the requirements of the API physical properties to ensure successful and robust formulation and process designs.

An Artificial - Intelligent - Based System to Automate the Design of Complex Mechanical Products

Over the last decades, there has been growing pressure on industrial companies to offer to their costumers products with high quality, in the minimum deadlines and with reasonable prices. Since the design phase plays a key role to achieve these difficult goals, many traditional, DFX (Design For X) and integrated approaches have been proposed. However, many limits are still present. Thus, the main objectives of this work were first to identify these limits and then to overcome them by proposing and developing an automated framework for integrated product design. In this work, we automated the integrated DFMMA (Design For Materials, Manufacturing and Assembly) approach by developing an architecture composed of four levels, namely: the Common Information Modeling Level, the Selection Systems Level, the Inference and Computation Level and finally the Application Level. The proposed automated system is based on ontologies, on the CBR (Cases Based Reasoning) and the RBR (Rules Based Reasoning). The first main result obtained throughout the contributions consists on the integration of Manufacturing process selection, Assembly solution selection and materials selection in one integrated design approach. The second main result obtained consists on the exploitation of all the previous design studies developed by the design team and the ability to reuse the designers experience throughout the case based reasoning used in the proposed architecture. Another important result consists on the formalization and the automation of the execution of the design rules and the ability to infer new results and to check inconsistencies in the developed product using the data and information modeled in the ontological model and throughout the Cases Based Reasoning that we have incorporated in the developed approach. In this way, the redundancy in work and the difficulties faced in case of having a high number of design alternatives are avoided. Consequently, the product quality increases and wastes of time and money decrease. Finally, to validate the functioning and the efficacy of the proposed DFMMA system, an application on the design of a complex mechanical product is developed in the end of the work.

A SHORT REVIEW ON ADVANCEMENT IN FAST DISSOLVING ORAL THIN FILMS

The pharmaceutical industry is pursuing the development of thin films as a novel method of drug administration. Thin films as an alternative to standard dosage forms have been described. They are a very adaptable platform capable of producing immediate, local, or systemic effects. Additionally, these systems are self-administered, which is advantageous for patients with dysphagia, elderly, pediatric, or bedridden patients and those who cannot administer with water. Thin film drug delivery methods are available for oral, buccal, sublingual, ophthalmic, and transdermal administration. This review explores oral thin films in all of their elements from a contemporary standpoint and provides insight into the world's expanding market share due to the expansion of study areas and technical advancements. Simultaneously, it presents an overview of the essential parameters that affect formulation design that affects thin films, including thin-film design, anatomical and physiological constraints, and the selection of suitable manufacturing processes, characterization methodologies, and the physicochemical properties of polymers and drugs are all covered in this section. Additionally, it provides insight onto the most recent thin-films produced by various pharmaceutical companies. KEYWORDS: Fast dissolving films, patient compliance, dysphagia, oral, buccal,sublingual.

Decision Support Methods in Manufacturing Process Selection: A Review of Recent Advances, Challenges, And Opportunities

Decision Support Methods in Manufacturing Process Selection: A Review of Recent Advances, Challenges, And Opportunities

Design and manufacture of a self-supporting racing motorcycle seat made on carbon fiber

This work presents the design and manufacture of the structural tail (subchassis+seat) of a racing motorbike which has participated in the MotoStudent 2016 edition, held in October 2016 on the Alcañiz circuit, representing the University of Malaga. Two motorcycles were presented, one inside the Petrol category (4 stroke engine and 250 cc) and another one in the Electric category. It is a self-supporting structure that replaces the use of the traditional subchassis and seat, in order to save weight. As a material we selected a 2x2 twill carbon fabric 3K, 200 g/m2 and Resoltech 1070/1074 epoxy resin. The selected manufacturing process has been manual molding and vacuum bag. Taking into account the estimated fiber percentage, the properties of the elemental sheet of composite material have been estimated using micromechanical models. These properties have been implemented in the finite element program Patran-Nastran for the optimization of the part. Once it has been designed, a model of the part has been fabricated on MDF wood which has been used to manufacture the mold of the piece in fiberglass. The designed part was homologated by the organization of the competition. The developed part is 50% lighter that previous solution. The manufactured mold allows to produce more pieces with the consequent cost reduction.

A Pilot Study on Machining Difficult-to-Cut Materials with the Use of Tools Fabricated by SLS Technology.

The growing use of contemporary materials in various industrial sectors, such as aerospace, automotive, as well as the oil and gas industry, requires appropriate machining methods and tools. Currently, apart from the necessity to obtain high-dimensional and shape accuracy, the efficiency and economic aspects of the selected manufacturing process are equally important, especially when difficult-to-cut materials, such as hard and brittle ceramics, have to be machined. In the research presented in this paper, a prototype tool fabricated from polyamide powder by the SLS method was used in flat-lapping of Al2O3 ceramics, showing the promising potential and efficacy of rapid tooling and manufacturing in the area of abrasive machining. The influence of the selected input process factors, such as machining time, the type of abrasive suspension, kinematic parameters, and unit pressure, on technological effects, was analyzed. The microscopic observations of the active surface of the prototype tool showed its reinforcement with loose diamond abrasive particles (size D107), resulting in the effective material removal and improved surface finish of Al2O3 ceramic samples. The directions for further development of tools fabricated by the SLS method for applications in abrasive machining were also envisaged by the authors.

A new design guideline development strategy for aluminium alloy corners formed through cold and hot stamping processes

In recent sheet metal forming research, efforts have been largely focused on determining optimum processing parameters, while intuitive guidelines to efficiently develop feasible component geometries are rarely considered. Consequently, there are currently no suitable design support tools that can guide component designers using the most recent, and therefore unfamiliar, sheet metal manufacturing technologies. This paper aims to address this bottleneck by proposing a strategy for the creation of early stage manufacturing design guidelines for the common limiting design requirement of deep corners. Aluminium alloys formed under both cold, and elevated temperature working conditions are considered. A new methodology to simplify the analysis of complex viscoplastic behaviour of aluminium alloys at elevated temperatures into an equivalent strain hardening response is presented. The effects and trends of the deep corner geometry and simplified material hardening characteristics on the post-form thinning distribution are identified. New equation sets are proposed which model the identified trends and enable the development of intuitive design maps. Following the approach proposed in this paper, an awareness of the available design envelope can be created at the early stages of a design process to guide component design, material, and manufacturing process selection decisions.

Multivariate manufacturing process planning for aircraft airframe production based on weighted criteria analysis

This paper deals with technological and operational aspects of manufacturing process planning for multiple values of decision parameters. A discrete parametric model is proposed to generate multiple process plans for a given or proposed production system. The model is based on generating graphs for possible manufacturing process operations and production system capabilities. An automated platform-based system is built around this model to generate and analyze multiple manufacturing process plans based on the chosen priority criteria. The analyses are based on estimating distances in constructed graphs and several sets of priorities for final assembly production systems as well as parts suppliers. Both manufacturing process selection and production systems architecture used in this model are specifically adapted for the aerospace industry.

Integrating optimal process and supplier selection in personalised product architecture design

A key enabler for personalised product design is an open product architecture that allows the integration of personalised modules to create unique products. Decisions regarding product variety, module combinations, and configurations for personalised modules need to be coordinated with the decisions of manufacturing process and supplier selection when developing personalised product architectures. Conventionally, product architecture, processes, and suppliers are independently determined at different product development stages. However, this sequential design process lacks connection between product architecture, process, and supplier, and may lead to suboptimal or even infeasible design solutions with compromised performance. In this study, a concurrent optimisation approach is proposed to integrate manufacturing process and supplier selection into personalised product architecture design. A cost model is developed as a nexus of product architecture, process, and supplier. Then, a mixed-integer optimisation model is established to maximise the potential profit of a product family based on a profit formulation that incorporates customer preference, process resource, supplier, and manufacturing cost. A genetic algorithm is utilised to solve this optimisation problem. The method is demonstrated on the architecture design for a family of personalised bicycles. The result shows that concurrent optimisation can achieve design solutions with higher profitability compared to sequential design strategies.

Current Overview of Oral Thin Films.

The pharmaceutical industry is attempting to discover thin films as a new drug delivery system. Thin films have been described as an alternative approach to conventional dosage forms. They are a versatile platform that provides fast, local, or systemic effects. Additionally, these systems can be easily applied by themselves, especially for dysphagia patients, geriatric, pediatric, or bedridden patients, as well as patients who cannot easily access water. These drug delivery systems can be administered in various ways such as orally, buccally, sublingually, ocularly, and transdermally. This review examines oral thin films in all aspects from today's point of view and gives an idea about the growing market share in the world due to the increase in research fields and technological developments. At the same time, it provides an overview of the critical parameters associated with formulation design that affect of thin films, including the design of thin films, anatomical and physiological limitations, the selection of appropriate manufacturing processes, characterization techniques, and the physicochemical properties of polymers and drugs. It also provides insight into the latest thin-film products developed by various pharmaceutical companies.

Methodology for integrated additive-subtractive process chain generation

The production share of laser powder bed fusion increases in industrial application and single piece and small series production are core markets. Still, many process steps in the field of additive manufacturing are manually operated, especially in post-processing. Additionally, it is not possible to achieve tight dimensional tolerances or low surface roughness which are necessary for typical mechanical parts. Hence, a process chain has to be set up to combine the design flexibility and function integration capabilities of AM with further machining technologies to achieve workpiece requirements. As L-PBF has some particular properties and process parameters influencing post-processing, an individual approach for process chain generation is needed. These properties and parameters are, in particular, support structures and free positioning options within the build chamber of the AM machine. Both properties have a major influence to post-processing and have to be addressed in machine selection, clamping options, processing steps and workpiece description. The approach shows how an additive manufactured workpiece can be described taking into account the complex part consisting of workpiece, support structures and substrate plate. Further, kinematic limitations for further processing are added as meta-information and workpiece requirements and machine performances are compared for a manufacturing process selection for further processing. Based on technological and economical parameters a manufacturing process selection is performed. Finally, improved parameters are suggested to optimize the L-PBF process with regard to further processing. So, the L-PBF process design can combine AM parameters with further processing parameters to improve the whole process chain. The methodology shall be implemented in a software tool to simplify the practical application.

A method for determining equivalent hardening responses to approximate sheet metal viscoplasticity

Recently developed elevated temperature metal forming technologies improve material formability and address the springback issues of cold forming. However, the behaviour of alloys at elevated temperatures is viscoplastic and therefore considerably more complex than under cold forming conditions. This complex behaviour creates a barrier for industrial designers when designing for elevated temperature processes, and therefore leads to these processes often being overlooked. To overcome this barrier, a new method is proposed here to determine simpler strain hardening responses that are equivalent to the viscoplastic responses of alloys at elevated temperatures. The equivalent hardening responses are expressed by single material hardening curves and their hardening exponents are taken as parameters to approximate sheet metal viscoplasticity. This method therefore makes it possible to develop early-stage design guidelines that consider different materials and stamping processes. The method was successfully applied to two viscoplastic alloys under hot stamping conditions to determine equivalent hardening responses. The feasibility of the method has been assessed through comparing finite element simulations using the determined equivalent material models with ones using viscoplastic models. The result showed that the thinning distributions obtained were consistent in both cases, providing evidence that the method can be applied to a range of component designs.•The proposed equivalent material models are simpler than existing viscoplastic material models and can be derived directly from experimental stress-strain data.•Creating design guidelines from equivalent hardening exponents enables a straightforward way to compare between cold and hot stamping capabilities. This comparison makes it possible to make manufacturing process and material selection decisions quickly and effectively at the onset of a design process.•Design guidelines enabled by the proposed method are critical resources to encourage the uptake of new elevated temperature metal forming technologies that facilitate lightweighting and improved environmental efficiency.

A decision support method for knowledge-based Additive Manufacturing process selection

Additive Manufacturing (AM) technologies and materials are more mature than ever; however, industrial AM use is still low. Lack of knowledge among potential users is a key barrier to AM uptake. There is therefore a significant need for methods and tools that will enable potential users to effectively identify the most appropriate materials and subsequently select the AM process that best fits their techno-economic requirements. This work presents a method for assisting potential users in the evaluation and process selection for AM. The method comprises four distinct Steps. Step 1 regards material selection, Step 2 examines AM process suitability, and Step 3 searches for suitable machines. The combined output of Step 1, Step 2, and Step 3 consists of several alternative paths, which are subsequently evaluated and classified in Step 4, based on multiple user-defined criteria.

Manufacturing of fiber reinforced polymer by using VARTM process: A review

The selection of manufacturing process plays a vital role in complex and large composite parts. VARTM process is one of the open mould composite manufacturing process which is highly used for manufacturing large composite parts. It is operated at atmospheric pressure and room temperature therefore, it is easy to control. In this process, the part thickness variation, compaction pressure and volume fraction are the process parameter. In this paper, the review of VARTM process has been carried out including its advantages and disadvantages. The step-wise experimental process has been described in detail. The relationship of process parameters have been described in details with equation. This review covered behavior of process parameters under dry and wet loading, point and line source of resin infusion, w/HPM and w/o HPM, variation of compaction pressure, adding the number of layers. The simulation approached for resin flow and pressure variation in composite component have been analyzed. The pressure distribution and resin flow have been validated with simulation approach. The dimension accuracy of VARTM process has been compared with other composite manufacturing processes.

Elimination of casting defects induced by cold box cores

One of the challenges of foundry industries is rejection of casting caused by porosity defects. Of the many factors, proper selection of core manufacturing process has higher impact on the reduction of porosity defects in castings. Cold box core making processes widely used by foundry industries to produce cores because of its good productivity and ability to produce complex designed cores. However, the probability of porosity defect in castings produced using cold box cores is higher than that of other processes. Globally, research is being carried out to solve the porosity defects in castings. However, complexity of the process and involvement of more process variables necessitate identification of root causes of the defects. This work aims at resolving the porosity defect in castings, when cold box core is used. Cores produced by furan core making process, which rarely results in porosity defects, was set as standard for testing the effectiveness of cores produced by cold box core making process. The results indicate that considerably high nitrogen content in the charge raw material in secondary iron making foundries enables reaction of metal with core (binder). Consequently, porosity arises in castings. The remedial measures to control the nitrogen content ensured casting rejections less than 7% in the foundry.

Computer Aided Selection of Optimal Non-Traditional Mechining Processes (Dept.M)

Manufacture of a product in a desired shape and size with specific characteristics and properties depend not only on the design of the product but also on the selection of the appropriate manufacturing process(es) that requires knowledge about various available alternatives. This paper presents a software for selecting an optimal non-traditional machining process(es). It has been developed using MATLAB, version (V7.8) release (R2009a), as programming language with the help of graphical user interface (GUI), visual aids, and fuzzy logic toolboxes. The selection procedures are based on elimination and ranking technique, and have been tested with a case study.

Research on the effect of structural and material parameters on vibrations based on quasi-static model of bearings

Variable compliance vibration is an inevitable source of the parametrically excited factors of rolling bearing–rotor system under the effect of only a limited number of rolling elements to carry the loads. Based on the quasi-static model of ball bearing, the mechanism of time-varying stiffness is studied and the effects of external load, rotational speed, geometric structure of the bearing and material parameters on the time-varying stiffness and relative variation of stiffness are analyzed quantitatively. Results show that load redistribution in bearing caused by the change of ball spatial position is the direct cause of the time-varying stiffness. Rotational speed, the number of balls and diameter have great effect on varying compliance vibration compared with external load and material parameters. In order to reduce the vibration, axial preload, contact angle, ball diameter and density should be appropriately increased, raceway groove curvature radius and radial load should be reduced, and the optimal number balls and rotational speed can be obtained according to the single-variable optimization method. The results provide theoretical basis for the structural design, material and manufacturing process selection.