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Rapid tooling (RT) integrated with additive manufacturing technologies have been implemented in various sectors of the RT industry in recent years with various kinds of prototype applications, especially in the development of new products. The purpose of this study is to analyze the current application trends of RT techniques in producing hybrid mold inserts.

The direct and indirect RT techniques discussed in this paper are aimed at developing a hybrid mold insert using metal epoxy composite (MEC) in increasing the speed of tooling development and performance. An extensive review of the suitable development approach of hybrid mold inserts, material preparation and filler effect on physical and mechanical properties has been conducted.

Latest research studies indicate that it is possible to develop a hybrid material through the combination of different shapes/sizes of filler particles and it is expected to improve the compressive strength, thermal conductivity and consequently increasing the hybrid mold performance (cooling time and a number of molding cycles).

The number of research studies on RT for hybrid mold inserts is still lacking as compared to research studies on conventional manufacturing technology. One of the significant limitations is on the ways to improve physical and mechanical properties due to the limited type, size and shape of materials that are currently available.

This review presents the related information and highlights the current gaps related to this field of study. In addition, it appraises the new formulation of MEC materials for the hybrid mold inserts in injection molding application and RT for non-metal products.

To provide a systematic framework for mold designers, that can be used for rapid tooling (RT) process selection and prioritization of process parameters.

This paper presents a QFD‐AHP methodology which has three phases. The first phase involves prioritizing the tooling requirements (driven by customer preferences) against a set of die/mold development attributes (such as product material, geometry, and die material and production order) through pair‐wise comparison using analytical hierarchal process (AHP). These priority ratings are used for selecting the most appropriate tooling process using quality function deployment (QFD) in the second phase. Finally, QFD is used again for identifying critical process parameters (such as layer thickness, scan pitch and laser power) for the selected RT process.

The QFD‐AHP methodology has been illustrated with industrial examples on RT for molded parts. The molds were fabricated using direct metal laser sintering and spray metal tooling processes, for example, 1 and 2, respectively, to prove that the methodology can be easily implemented in tool rooms. The issues noted in these experimental studies are also discussed for the benefit of researchers.

The capabilities of the RT processes presented in the paper reflect the experience of the research team in RT development. The QFD‐AHP methodology will give progressively better results with a growing body of RT process knowledge.

This investigation is a key step towards the goal of developing a comprehensive system for RT process selection and manufacturability evaluation. The mold designer can use this QFD‐AHP process selection methodology, prior to detailed manufacturability analysis, to better realize the benefits of RT technologies.

The proposed QFD‐AHP methodology is a new approach for the tooling process selection domain, and has not been reported earlier; this can be easily used for similar applications for any manufacturing domain.

Rapid prototyping technologies have introduced a new generation of rapid tooling processes. Many of these rapid tools have been used for injection moulding where the thermal properties of the tool material are critical to the quality of parts produced. Rapid tools are often made from materials with substantially different thermal properties than conventional metal tools. Engineers wishing to make use of these technologies to produce technical prototypes must be aware of the effect this will have on final part properties. Some previous research has been undertaken in this area. Reviews the work done in the field of rapid tooling used for injection moulding. The review shows that, whereas a range of techniques and final part materials has been studied, the results obtained are incomplete and often unexplained. The authors draw conclusions as to why this is so and go on to identify areas for further work that will be pursued.

The strategic integration of rapid prototyping and rapid tooling is being used for getting product to the market quickly by resolving a long‐standing conflict between design and manufacturing. Currently rapid tooling can be produced at such reduced cost and time that the tool is considered to be disposable. The ability to produce inexpensive tooling allows the life cycle to be fundamentally changed, incorporating the concept and tooling review into one development phase and allowing both design and manufacturing requirements to be identified. This approach has allowed management to release product based on competitive market strategy rather than an estimated deadline.

To provide an innovative way for manufacturing in which the integration of rapid technologies is simultaneously used methodologically in real‐time for the rapid product and process development (RPPD).

A range of related works are discussed and an experimental implementation of the RPPD methodology is described for composite functional prototype design and rapid manufacturing (RM). The simultaneous integration of VP/RP/RT/RE/RM technologies consolidates a powerful methodology to achieve the RPPD objectives.

The RPPD developed methodology takes advantage of both virtual prototyping (VP) and physical prototypes made by rapid prototyping (RP) technology to evaluate performances and design ergonomic aspects. The increasing needs to reduce lead‐time and costs have direct converting RP in rapid tooling (RT) technology for RM. Furthermore, to verify the parts and tools geometry accuracy the simultaneous use of scanning techniques for metrology control aided by reverse engineering (RE) as allow decreasing the RPPD time.

This paper evaluated RPPD results and the metrology control plotted in error distribution function and cumulative error distribution histograms validate the best practice developed that industrial manufacturers could implement allowing time and costs reductions.

The selective laser sintering (SLS) process is one of the leading rapid prototyping techniques. This paper presents two rapid tooling (RT) methods based on the SLS process. The first method employs the SLS process to build tooling inserts in copper polyamide that can be used for fabrication of a limited number of pre‐production parts in the same material and manufacturing process as the final production parts. The second method, the RapidTool^TM process, is a RT solution for manufacture of pre‐production and production tools for injection moulding and die‐casting. The paper also discusses the applications and limitations of these RT methods.

The purpose of this paper is to present the results of an investigation on the straightness, flatness and circularity achievable on two direct RT methods: direct metal laser sintering (DMLS) and stereolithography (SLA).

The steps included manufacturing of samples in eight custom designs with widely used geometric features, intelligent sampling of measurement data, and estimation of corresponding form tolerance by the least square method (LSM). The region elimination adaptive search‐based sampling method involved selecting additional sampling points around the maximum deviation in both positive and negative directions from the corresponding reference feature. The LSM solutions, which are commonly used in metrology, are used to estimate the form tolerances considering the best points along with initial measurement data points.

Application of the region elimination search‐based sampling method enables form tolerance estimation from a limited number of sample measurements. The study of the DMLS and SLA processes suggested that form accuracy of SLA samples are relatively poor, though their dimensional accuracy is much better than DMLS.

This paper was focused on estimating the form tolerances based on limited number of measurement data using region elimination search‐based sampling technique. It was assumed that build process parameters suggested by the material and RP systems vendors gives optimum results, presently it does not cover the effect of geometry and other causes of errors on form accuracy.

There are two major applications of this investigation and the corresponding knowledge base: evaluating the process capabilities of different rapid tooling processes for comparison and for selecting an appropriate process; and allocating tolerance based on manufacturability considerations, so that the designs are compatible with the process, leading to fewer iterations. A similar approach can be used for updating the capabilities of an improved process as well as include newer processes to develop a comprehensive database of RT process capabilities.

In most of the previous benchmarking studies, a given RT process is compared with conventional practice or a limited number of other RT processes, the capabilities in terms of dimensional accuracy, form tolerance, and surface properties (surface finish, wear, and scratch resistance) have not been studied very well. To the best of authors' knowledge, no efforts have been made to estimate form tolerances of the parts or tooling produced by rapid prototyping and tooling processes. Application of the region elimination search‐based sampling technique enables estimation of form tolerances that saves costly experimentations. It appears to be completely new in the rapid prototyping and tooling domain.

The purpose of this study is to highlight the direct fabrication of rapid tooling (RT) with desired mechanical, tribological and thermal properties using fused deposition modelling (FDM) process. Further, the review paper demonstrated development procedure of alternative feedstock filament of low-cost composite material for FDM to extend the range of RT applications.

The alternative materials for FDM and their processing requirements for fabrication in filament form as reported by various researchers have been summarized. The literature demonstrates the role of various post-processing techniques on surface finish of FDM prints. Further, low-cost materials for feedstock filament have been investigated experimentally to check their adaptability/suitability for commercial FDM setup. The approach was to realize the requirements of FDM (melt flow rate, flexibility, stiffness, glass transition temperature and mechanical strength), necessary for the successful run of an alternative filament. The effect of constituents (additives, plasticizers, surfactants and fillers) in polymeric matrix on mechanical, tribological and thermal properties has been investigated.

It is possible to develop composite material feedstock as filament for commercial FDM setup without changing its hardware and software. Surface finish of the parts can further be improved by applying various post-processing techniques. Most of the composite parts have high mechanical strength, hardness, thermal stability, wear resistant and better bond formation than standard material parts.

Future research may be focused on improving the surface quality of parts fabricated with composite feedstock, solving issues related to the uniform distribution of filled materials during the fabrication of feedstock filament which in turns further increases mechanical strength, high dimensional stability of composite filament and transferring the technology from laboratory scale to various industrial applications.

Potential applications of direct fabrication with RT includes rapid manufacturing (RM) of metal-filled parts and ceramic-filled parts (which have complex shape and cannot be rapidly made by any other manufacturing techniques) in the field of biomedical and dentistry.

This new manufacturing methodology is based on the proper selection and processing of various materials and additives to form high-performance, low-cost composite material feedstock filament (which fulfil the necessary requirements of FDM process). Finally, newly developed feedstock filament material has both quantitative and qualitative advantage in RT and RM applications as compared to standard material filament.

The purpose of this paper is to apply rapid prototyping (RP) philosophy as a technology transfer in industries to take its time and cost‐effective advantages for development of rapid tooling (RT).

Experimentations are performed for development of RT for sand casting, investment casting and plastic moulding applications.

This paper reports the procedures developed for manufacture of production tooling using RP. A cost/benefit model is developed to justify implementation of RP as a technology transfer in industries.

The examples are limited to parts build by fused deposition modelling RP process. However, the concepts experimented may be applied for other RP processes.

RP has proved to be a cost‐effective and time‐efficient approach for development of RT, thereby ensuring possibility for technology transfer in casting as well as plastic industries.

This is the pioneer attempt towards quantifying RP benefits, in view of technology transfer. This paper presents original case studies and findings on the basis of experimentations performed in foundries.

A continuous positive airway pressure (CPAP) device is one of the main treatments for obstructive sleep apnea (OSA) patients. Most patients treated by this method complain about the comfortableness of the mask, but the commercial mask cushions are only available in fixed sizes. Therefore, the purpose of this paper is to apply the rapid tooling (RT) technique to manufacture customized nasal mask cushions, to increase the performance and with price competitiveness.

The patient's face was first duplicated twice by Hygrogum and plaster. The face model, on which the cushion CAD design was based, was digitized by the reverse‐engineering technology. The RT of the cushion was then designed and manufactured by two rapid prototyping techniques – Objet's PolyJet and shape deposition manufacturing (SDM). Finally, silicone was cast into the RT to obtain customized cushions. The customized cushion was compared with two other commercial cushions through fit testing and cost estimation.

The proposed approach can successfully manufacture customized cushions within a day. The SDM process has advantages in this application over Objet's system. The fit testing showed that the fit factor of the customized cushion was better and less loading was required, which should lead to great improvement in the patient's comfort. Moreover, the price‐to‐performance ratio of the customized cushion can be lower than the commercial ones if more than three cushions were made by a single rapid tool.

This paper has proposed a new application of RT on customized nasal mask cushions for CPAP devices. The customized cushion has lower price‐to‐performance ratio and the cost remains competitive.