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This paper details the development of a rapid tooling manufacturing route for the gravity and high‐pressure die‐casting industries, resulting from an EPSRC funded collaborative research project between the Universities of Warwick, Loughborough and DeMontfort, with industrial support from, amongst others, MG Rover, TRW Automotive, Sulzer Metco UK Ltd and Kemlows Diecasting Products Ltd. The developed process offers the rapid generation of mould tools from laser‐cut laminated sheets of H13 steel, bolted or brazed together and finish machined. The paper discusses the down‐selection of materials, bonding methods and machining methods, the effect of conformal cooling channels on process efficiency, and the evaluation of a number of test tools developed for the industrial partners. The paper also demonstrates the cost and time advantages (up to 50 and 54 per cent, respectively) of the tooling route compared to traditional fabrication methods.

This paper proposes sheet thickness determination in manufacturing of laminated dies as an optimization problem. The aim of this optimization procedure is finding the best set of thicknesses which minimizes the volume deviation between actual computer‐aided design (CAD) model and assembled slices.

This works uses a modified version of genetic algorithms for the optimization purpose. Each set of thicknesses that can cover the whole CAD model surface is considered as a chromosome. Genetic operators such as crossover and mutation have to be modified to be used in this application.

A new method for finding the total volume deviation between assembled slices and the actual CAD model was developed in this research. On the other hand, the results show how the program can automate the slice plane locations search process.

Premature convergence does not allow the algorithm to search the entire solution space before getting trapped in a local optimum. Even the mutation operator cannot postpone this untimely convergence.

The proposed method is a good substitute for the manual methods that are currently used in industry. These experience‐based methods are mostly based on the decision made by a well‐trained technician on picking up the thicknesses for a specific CAD model.

This is the first attempt at optimizing the slicing method in laminated tooling. Other methods are mostly based on rapid prototyping (RP) and they are not applicable in the laminated tooling process since, despite RP, here not all optimization outputs can be used in practical procedure.

The purpose of this paper is to review additive and/or subtractive manufacturing methods for metallic objects and their gradual evolution from prototyping tools to rapid manufacture of actual parts.

Various existing rapid manufacturing (RM) methods have been classified into six groups, namely, CNC machining laminated manufacturing, powder‐bed technologies, deposition technologies, hybrid technologies and rapid casting technologies and discussed in detail. The RM methods have been further classified, based on criteria such as material, raw material form, energy source, etc. The process capabilities springing from these classifications are captured in the form of a table, which acts as a database.

Due to the approximation in RM in exchange for total automation, a variety of multi‐faceted and hybrid approaches has to be adopted. This study helps in choosing the appropriate RM process among these myriad technologies.

This review facilitates identification of appropriate RM process for a given situation and sets the framework for design for RM.

Due to an uncertainty between actual model and assembled slices, there is always an extra material on assembled slices in laminated tooling. Therefore, a post processing, usually CNC machining, is required to remove this extra material and reach the near net shape surface for final product. One of the issues in laminated tooling is to minimize the amount of this extra material and reduce the cost of the post processing. Direction of slicing is an important parameter in this issue. This research aims to introduce a method to find the best slicing direction based on CAD model surface geometry and minimize the amount of the extra material in the assembled slices. Researches on the best slicing direction investigation so far were mostly based on the extra volume calculation for a number of candidate directions. Since the time needed for the extra volume calculation is proportionally high, the number of candidate directions to be investigated was usually limited, whereas, in the proposed method, the best slicing direction is found based on CAD model surface geometry and there is no need to find the actual amount of the extra volume. Moreover, the suggested method is developed to the cases where having more than one slicing direction is desirable for more reduction in the amount of the extra volume. The proposed optimization method can be used to find the best slicing direction in laminated tooling. Moreover, the ability to suggest multiple slicing directions can provide more reduction for the amount of the extra material. However, the number of candidate directions in the case of multiple slicing directions is limited due to joining problems in laminated tooling.

The investigation is based on the situation of normal vectors on CAD model surface. The CAD model surface is considered as a combination of planar tiles and all normal vectors of these tiles are considered as the candidate directions. This provides a number of candidates that can cover almost all possible slicing directions. The best slicing direction is then found by estimating the amount of the extra material produced on the tiles by each normal vector.

The proposed method applied to some examples. The case studies included the simple predictable models to qualify the reliability of the proposed method. Also more applicable examples were provided to show how the suggested method acts in real cases.

The proposed method can be applied to each and every CAD model. Therefore, there is no limitation with regard to the type of model which can be investigated by the proposed method. However, there is limitation on the number of times the building direction can be changed in laminated tooling.

The proposed method can be employed to reduce the post processing time in laminated tooling.

Following the prior study researchers conducted in optimization of laminated dies, another parameter, slicing direction, is considered in this research. This brings a new approach on laminated dies optimization to reduce the production cost.

The purpose of this paper is to present the utilities of packaging and PCB fabrication processes for manufacturing micro electromechanical systems (MEMS) and its package for sensing and actuation applications.

A broad array of manufacturing approaches available in the packaging industry, including lamination, lithography, etching, electroforming, machining, bonding, etc. and a large number of available functional materials such as polymers, ceramics, metals, etc. were explored for producing functional microdevices with greater design freedom.

Good quality MEMS devices can be manufactured using packaging style fabrication, particularly using stacks of laminates. Furthermore, such microdevices can be built with a high degree of integration, pre‐packaged, and at low cost.

Further manufacturing research work should be undertaken in collaboration with the PCB and packaging industries, which stand to benefit greatly by expanding their offerings beyond serving the semiconductor industry and developing their own integrated MEMS products.

The paper presents examples of basic packaging fabrication processes for producing 3‐D structures and free‐standing structures, and a new MEMS manufacturing paradigm to build micro‐electromechanical (MEMS) for biomedical, optical, and RF communication applications.

Lastform, a three year EPSRC (IMI) programme, has investigated metallic laminating techniques to produce large‐scale production capable tooling. This work is intended as an overview of the research and development performed at the University of Warwick’s Warwick manufacturing Group. The programme was a collaboration between seven industrial partners and three universities with each university having a discreet area of research. The focus at Warwick was to establish robust methods of joining metal sheets to form tools for different production processes. Bonding mediums, test parts for process evaluation, sample tools and production tools are described. The advantages of metal laminating for different processes are evaluated. Results include reduced lead‐time and cost savings and enhanced processing capability by the use of conformable heating or cooling channels.

This paper seeks to detail the fabrication of a glass‐ceramic substrate, based on the LiO₂‐ZrO₂‐SiO₂‐Al₂O₃ (LZSA) system, by laminated object manufacturing (LOM) using water‐based cast tapes.

Small amounts of ZrSiO₄ were added to control the thermal expansion coefficient (TEC) of the original glass‐ceramic (LZSA5Zr: LZSA+5 wt% ZrSiO₄). In order to verify the influence of the amount and nature of crystalline phases on the thermal and dielectric behavior of the material, LZSA and LZSA5Zr laminates were sintered at 700°C for 30 min and crystallized at either 800 or 850°C for 30 min.

LZSA laminates (sintered and crystallized at 700 and 800°C, respectively) exhibited a relative density of ∼90 percent, a dielectric constant of 8.39, a dielectric loss tangent of 0.031 and TEC of 5.5×10⁻⁶ K⁻¹ (25‐550°C). The addition of 5 wt% ZrSiO₄ to original LZSA glass‐ceramics led to a nearly constant TEC value of 6×10⁻⁶ K⁻¹ throughout the whole temperature interval (25‐800°C). Dielectric properties of LZSA5Zr did not show any remarkable change when compared to original LZSA.

The thermal, mechanical and electrical properties of LZSA glass‐ceramic laminates fabricated by LOM makes them potential candidates for substrate applications.

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.

The purpose of this paper is to improve the yield of a particular model of a car windshield, as the organization faces losses due to poor performance and rejection.

The Six Sigma DMAIC (define, measure, analyze, improve and control) methodology is used to reduce variation and defects in the process. It is a methodology based on data-driven and fact-based analysis to find out the root cause of the problem with the help of statistical analysis. A worst performing model is selected as a case study through the scoping tree. The preprocess, printing, bending and layup process defects are reduced by analyzing the potential causes and hypothesis testing.

This paper describes Six Sigma methodology in a glass manufacturing industry in India for automotive applications. The overall yield of a car windshield achieved 93.57 percent against the historical yield of 88.4 percent, resulting in saving 50 lacs per annum. Due to no rework or repairing in the glass, low first-time yield causes major losses. Process improvement through focused cross-functional team reduces variation in the process. Six Sigma improves profitability and reduces defects in the automotive glass manufacturing process.

This case study is applied in automotive glass manufacturing industries. For service and healthcare industries, a similar type of study can be performed. Further research on the common type of processor industry would be valuable.

The case study can be used as a problem-solving methodology in manufacturing and service industries. The tools and techniques can be used in other manufacturing processes also. This paper is useful for industries, researchers and academics for understanding Six Sigma methodology and its practical implementation.

This case study is an attempt to solve automobile glass manufacturing problems through DMAIC approach. The paper is a real case study showing benefits of Six Sigma implementation in the manufacturing industry and saving an annual cost of 50 lacs due to rejections in the process.

The purpose of this paper is to study the internationalisation of an Indian company. It examines how a company from an emerging market becomes a leading player in the global packaging (tube) industry.

This is a case study approach for studying the process of internationalisation in one particular firm.

The case study shows how a company based in an emerging market converts tubing industry into an innovative and high‐tech industry and becomes a leading palyer. The company has followed the traditional stages process of internationalisation and accumulated learnings in the process.

The traditional stages model of internationalisation and focus on accumulating learnings in the process and using them has helped the firm and other firms and managers can learn from this case. For academicians, it further support the famous stages approach of internationalisation process.

Increasing number of companies from emerging markets are now turning to international markets and in the process turning into multinationals. These firms are giving tough competition to established multinational companies from developed countries. Most of the research and case studies focus on big firms like Lenevo etc but there are increasing number of firms like Essel Propack which are also a big success in international markets.