Technological Prototypes Research Articles

Process Capability Analysis of Vacuum Moulding for Development of Al-Al2O3 MMC

The purpose of the present study is to investigate process capability of vacuum moulding (VM) for development of Al-Al2O3 metal matrix composite (MMC). Starting from the identification of component, prototypes were prepared (with three different input parameters namely: vacuum pressure; component volume and sand grit size to give output in form of dimensional accuracy). Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the Al-Al2O3 MMC prepared. Some important mechanical properties were also compared to verify the suitability of the components. Final components produced are acceptable as per ISO standard UNI EN 20286-I (1995). The results of study suggest that VM process lies in ±4.5 sigma (σ) limit as regard to dimensional accuracy of Al-Al2O3 MMC is concerned. This process ensures rapid production of pre-series technological prototypes and proof of concept at less production cost and time.

Process capability study of rapid silicon moulding for plastic components

The purpose of the present study is to investigate process capability of rapid silicon moulding for plastic components. Starting from the identification of component, prototypes with two different type of plastic material were produced under different vacuum moulding conditions. Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the plastic components produced. Some important mechanical properties were also compared to verify the suitability of the components. Final components produced are acceptable as per ISO standard UNI EN 20286-I (1995) and DIN16901. The results of study suggest that rapid silicon moulding process lies in ± 4.5 sigma (σ) limit as regards the dimensional accuracy of plastic components is concerned. This process ensures rapid production of pre-series technological prototypes and proof of concept at less production cost and time.

Experimental Investigations for Rapid Moulding Solution of Plastics Using Polyjet Printing

Rapid prototyping (RP) has been in evidence for the past twenty years and is being widely used in diverse areas, from the building of aesthetic and functional prototypes to the production of tools and moulds for technological prototypes. The purpose of the present study is to experimentally investigate the rapid moulding (RM) solutions for plastic components using polyjet printing (PP) technique. Starting from the identification of component/benchmark, prototypes with three different type of plastic material were produced, at different orientation and support material. Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the plastic components produced. Some important mechanical properties were also compared to verify the suitability of the components. The study highlighted the best orientation, support material quantity and type of plastic material for the selected component from dimensional accuracy and economic point of view as RM solution for plastic components. This process ensures rapid production of pre-series technological prototypes and proof of concept at less production cost and time.

Experimental Investigations for Silicon Moulding Solution of Plastic Components

The purpose of the present study is to experimentally investigate rapid moulding solutions for plastic components using silicon moulding technique. Starting from the identification of component, prototypes with two different type of plastic material were prepared under different vacuum moulding conditions. Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the plastic components produced. Some important mechanical properties were also compared to verify the suitability of the components. The study highlighted the best settings of orientation and type of plastic material for the selected component from dimensional accuracy and economic point of view as rapid moulding solution for plastic components. Final components produced are acceptable as per IS standard UNIEN20286-I (1995). This process ensures rapid production of pre-series technological prototypes and proof of concept at less production cost and time.

English

In the present work, the most cost effective/best shell wall thickness of mould cavities has been compared with other available shell wall thicknesses for statistically controlled rapid casting solutions of zinc alloy. Starting from the identification of component/ benchmark, technological prototypes were produced at different shell thicknesses with three dimensional printing. The results of the study suggest that at the best shell wall thickness (7 mm) for zinc alloys, the rapid casting solution is statistically controlled, which is not observed for all shell wall thicknesses of mould cavities prepared with three dimensional printing.

Effect of Moulding Sand Properties on Cost Effective Hybrid Rapid Casting Solution for Zinc Alloy

The purpose of the present experimental investigations is to study the effect of moulding sand properties on reducing the shell wall thickness of mould cavity for cost effective, hybrid rapid casting solution of zinc alloy. Starting from the identification of component/benchmark, technological prototypes were produced, with three different moulding sands (dry, green and molasses), at different shell wall thickness of mould cavity using hybrid rapid prototyping technique (combination of three dimensional printing and conventional sand casting). Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings. The study suggested that for the shell thickness, having value less than the recommended one is more suitable from dimensional accuracy and economic point of view, for all three moulding sands. Further best shell wall thickness of the mould cavity for different moulding sands, for the selected component/benchmark has been highlighted for rapid casting solution of zinc alloy.

Effect of Work Piece Dimensions on Cost Effective Hybrid Rapid Casting Solution for Aluminium Alloy

The purpose of the present experimental investigations is to study the effect of work piece dimensions on reducing the shell wall thickness of mould cavity for cost effective, hybrid rapid casting solution of aluminum alloy. Starting from the identification of component/benchmark, technological prototypes with three different work piece dimensions (volume/ weight) were produced, at different shell wall thickness of mould cavity using hybrid rapid prototyping technique (combination of three dimensional printing and conventional sand casting). Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings. The study suggested that the shell wall thickness, having value less than the recommended one is more suitable from dimensional accuracy and economic point of view, for all three work piece dimensions (volume/ weight). Further best shell wall thickness of the mould cavity for different work piece dimensions of the selected benchmark has been highlighted for rapid casting solution of aluminum alloy.

Process capability study of polyjet printing for plastic components

The purpose of the present study is to investigate process capability of polyjet printing (PP) for plastic components. Starting from the identification of component, prototypes with three different type of plastic material were prepared at different orientations. Measurements on the coordinate measuring machine helped in calculating the dimensional tolerances of the plastic components produced. Some important mechanical properties were also compared to verify the suitability of the components. Final components produced are acceptable as per ISO standard UNI EN 20286-I (1995) and DIN16901. The results of study suggest that PP process lies in ±4.5sigma (σ) limit as regard to dimensional accuracy of plastic component is concerned. This process ensures rapid production of pre-series technological prototypes and proof of concept at less production cost and time.

Performance of 2nd generation CALICE/EUDET ASICs

The paper reviews the performance of the three ASICs : HARDROC2, SPIROC2 and SKIROC2 developed to readout the ILC calorimeter prototypes. The chips integrate 36 to 64 channels of front-end, digitization and backend electronics in SiGe 0.35 μm technology. This second version was found mature enough to be produced in several hundreds to equip large scale technological prototypes and establish the feasibility of these highly granular "imaging" calorimeters as required for particle flow algorithms at the ILC. The low noise and low power sequential readout as well as power-pulsing operation at detector level and in magnetic field are proven.

Study of statistically control rapid casting solution of aluminium alloys using three dimensional printing

The purpose of the present investigations is to study the feasibility of decreasing the shell wall thickness of mould cavity for economical and statistically controlled rapid casting solution of aluminium alloy using three dimension printing technology. Starting from the identification of component/benchmark, technological prototypes were produced at different shell wall thickness of mould cavity. Measurements on a coordinate measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings. The study suggested that the shell wall thickness, having value less than the recommended one is more suitable from dimensional accuracy and economic point of view. The result indicates that for the selected component/benchmark, at best set shell wall thickness (5 mm) of mould cavity, strong possibilities are observed for the process under statistical control in case of aluminium alloy.

An overview of three dimensional printing for casting applications

Rapid prototyping (RP) has been in evidence for the past 20 years and is being widely used in diverse areas, from the building of aesthetic and functional prototypes to the production of tools and moulds for technological prototypes. Among various RP techniques, three dimensional printing (3DP) is a relatively new form of RP. The present research paper provides an overview of RP process and specifically 3DP for shell patterns obtained from ceramic shells that can be built and then joined (as in the conventional process) to obtain the cavity for pouring metal for generation of cost effective prototypes for casting applications.

Effect of moulding sand on statistically controlled hybrid rapid casting solution for zinc alloys

The purpose of the present investigations is to study the effect of moulding sand on decreasing shell wall thickness of mould cavities for economical and statistically controlled hybrid rapid casting solutions (combination of three dimensional printing and conventional sand casting) for zinc alloys. Starting from the identification of component/ benchmark, technological prototypes were produced at different shell wall thicknesses supported by three different types of sands (namely: dry, green and molasses). Prototypes prepared by the proposed process are for assembly check purpose and not for functional validation of the parts. The study suggested that a shell wall with a less than recommended thickness (12mm) is more suitable for dimensional accuracy. The best dimensional accuracy was obtained at 3mm shell wall thickness with green sand. The process was found to be under statistical control.

Comparative Study of 3D Printing Technologies for Rapid Casting of Aluminium Alloy

The purpose of this study is to compare the efficacy of two rapid casting technologies, namely, ZCast process and investment casting based on 3D printing technique of rapid prototyping for casting of aluminium alloy. A standard procedure has been premeditated starting from the identification and design of benchmark. The concept was presented in physical form by producing prototypes to assess the impact of technology used on dimensional accuracy by assigning tolerance grades as per UNI EN 20286-1 ISO. Important mechanical properties were also compared to verify the suitability of the castings and further results are supported by microphotographs and radiography analysis. Best settings for the 3D printing machine and the minimum shell thickness for ZCast process are proposed which give the acceptable results as per IS casting standards. Two commercially available powders, namely, ZP14 (starch based) and ZP100 (plaster based) were infiltrated with two infiltrants, namely, acrylate and wax, resulting in four different material systems for making patterns for investment casting. For ZCast process the shells were printed in ZCast501 powder and were directly used as mould with sand support. The proposed rapid casting technologies based on 3D printing, proved to be effective for the production of cast technological prototypes in very short times avoiding any tooling phase and with dimensional tolerances that are completely consistent with metal casting processes.

Investigations for a statistically controlled rapid casting solution of lead alloys using three-dimensional printing

The purpose of the present investigation is to study the feasibility of decreasing the shell thickness for a statistically controlled rapid casting solution of lead alloy using three-dimensional printing technology. Starting from the identification of a component/benchmark, technological prototypes were produced with different shell thickness. Measurements on a coordinate measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings and further results are supported by microstructure analysis. The study suggested that the shell thickness having a value less than the recommended one is more suitable from a dimensional accuracy and an economic point of view. The provided data from the experimentation are extremely useful for the industrial application of the considered technology. The result indicates that at 1 mm shell thickness, the hardness of the casting improves from the recommended 12 mm. Further, production costs and production time have been reduced by 45.75 and 43 per cent, respectively, in comparison with the 12 mm recommended shell thickness.

Comparison of rapid casting solutions for lead and brass alloys using three-dimensional printing

The purpose of the present investigation is to study and compare the feasibility of decreasing the shell wall thickness for rapid casting solution of brass and lead alloys using three-dimensional printing (3DP) technology. Starting from the identification of components/benchmarks, technological prototypes have been produced at different shell thicknesses using lead and brass alloys. Measurements on a coordinate measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties are also compared to verify the suitability of the castings and further results are supported by microstructure analysis. The study suggested that the production of sound casting for minimum wall thickness depends on pouring temperature and weight density. It has been observed that IT grades comparable to machining can be obtained with 3DP for lower pouring temperature alloys. Further feasibility of obtaining minimum shell thickness is more dependent on pouring temperature than weight density. Based on improved dimensional accuracy and microstructure analysis, the saving of costs up to 45.75 per cent and time up to 43 per cent can be achieved over the recommended one in the case of lead alloy for the selected benchmark/component. For brass alloy casting saving of costs and time up to 40.05 and 32.84 per cent, respectively, has been achieved.

Investigations for statistically controlled rapid casting solution of low brass alloys using three dimensional printing

The purpose of the present investigations is to study the feasibility of decreasing the shell wall thickness of mould cavity for economical and statistically controlled rapid casting solution of low brass alloy using three dimension printing technology. Starting from the identification of component/benchmark, technological prototypes were produced at different shell wall thickness of mould cavity. Measurements on a coordinate measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings. The study suggested that for the shell thickness, having value less than the recommended one is more suitable from dimensional accuracy and economic point of view. The result indicates that for the selected component/benchmark, at best set shell wall thickness (2 mm) of mould cavity, hardness of the casting improves from recommended 12 mm. Also production cost and production time has been reduced by 40.05% and 32.84% respectively in comparison to 12 mm recommended shell thickness. Further, strong possibilities are observed for the process under statistical control for 2 mm shell thickness the in case of low brass alloy castings.

Experimental investigations for reducing wall thickness in zinc shell casting using three-dimensional printing

The purpose of this study is to verify the feasibility of decreasing the shell thickness in rapid casting (RC) process based on three-dimensional printing technology and to evaluate the dimensional accuracy, mechanical properties of RC solutions for the production of zinc-alloy casting. Starting from the identification of component/benchmark, technological prototypes were produced with different shell thickness. Measurements on a coordinate-measuring machine helped in calculating the dimensional tolerances of the castings produced. Some important mechanical properties were also compared to verify the suitability of the castings, and further results are supported by the radiography analysis. The study suggested that the shell thickness having value less than the recommended one is more suitable from dimensional accuracy and economic point of view. The provided data from the experimentation are extremely useful for the industrial application of the considered technology. The result indicates that at 7 mm shell thickness, hardness of the casting improved from the recommended 12 mm. Further, production cost and production time have been reduced by 41 and 37 per cent, respectively, in comparison with the 12 mm recommended shell thickness.

“I Wish We Could Get Together”: Exploring Intergenerational Play Across a Distance via a ‘Magic Box’

ABSTRACT It is well documented that ongoing social connection between the young and the elderly increase the sense of well-being of both parties. However it may be difficult to maintain and cultivate intergenerational relationships in which physical, temporal, or social distances exist between grandparents and their grandchildren. This paper outlines findings from an ethnographic research study which explores the nature of intergenerational play and interaction across a distance. Our aim is to understand playful engagement as a means for designing technologies that will support intergenerational play across a distance. The paper highlights examples of data produced by a small number of Australian families using cultural probes. This data originates from personal scrapbooks, the daily exchange of special items via a ‘Magic Box’ and from interviews with participants. The scrapbooks and ‘magic box’ methods, in particular, encouraged the exchange of a range of thought-provoking and non-traditional media. Much of this media was exchanged with a view to encouraging play or playful activity; however there were serious issues of family history, culture, and storytelling which underlay the selection of particular items. Items exchanged between distributed households included feathers, dolls, toys, food and letters. While all the exchanges were in some way indicative of the special relationships which existed amongst these diverse families, there are a number of themes which arise across the families. The paper illustrates that intergenerational play and communication are intrinsically intertwined with a range of themes including family history, culture, and storytelling; and familial ideas of magic, science, and fun. It is anticipated that the next phase of the research will produce suggestions for technological prototypes which might help to further support intergenerational exchanges across a distance.

3D printing technique applied to rapid casting

PurposeThe 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.Design/methodology/approachStarting 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.FindingsThe 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.Practical implicationsThe 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.Originality/valueThe 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.

Sharing Control: Contesting Distributed Computing

This paper examines distributed computing projects in which users allow their unused computing resources to be utilised by third parties. As well as being the latest manifestation of an internet gift economy, these projects represent technological prototypes for resource sharing over the internet — ideas that are being pursued by capital for different reasons. The resultant tension between gift and commodity has led to competing claims for control over spare processing power. This paper examines examples of distributed computing and conflicts that have arisen over its control.