Influence of mould material on ceramic disc dimensions in low-pressure injection moulding

2016 ◽  
Vol 231 (1-2) ◽  
pp. 187-195 ◽  
Author(s):  
Carlos A Costa ◽  
Carlos R Altafini ◽  
Fabio R Visioli ◽  
André P Baccin
Keyword(s):  
Cooling Rate ◽  
Injection Moulding ◽  
Low Pressure ◽  
Extraction Temperature ◽  
Mould Insert ◽  
Mould Material ◽  
Moulding Process ◽  
Pressure Injection ◽  
Injection Moulding Process ◽  
Geometric Deviations

This work presents a study regarding the influence of the cooling process, as a result of different mould insert materials, on ceramic parts dimensions obtained by low-pressure injection moulding process. Discs of ceramic with Ø80 × 2 mm, composed by 86 wt.% alumina (Al2O3) and 14 wt.% organic vehicle, were produced. An experimental injection mould was designed and manufactured with built-in heating and cooling systems, controlled by a DAQ (Measurement Computing – USB-TC) and thermocouples K type. Four types of insert materials were used: aluminium alloy (AA7075-T6), electrolytic copper, brass alloy (C36000) and SAE1045 steel. Tests were carried out considering injection moulding parameters constant, i.e. initial mould temperature, injection pressure and time and extraction temperature. All the post-process (debinding by wicking; final debinding and sintering) parameters were also kept constant. Parts were analysed considering dimensions, mass, geometry, visual aspects and defects. The results showed that the cooling rate resulting from the thermal conductivity of each material has influenced more significantly the dimensional shrinkage and mass reduction of the samples during the intermediate post-processes phases. The geometric deviations were different for each condition throughout the process and they increased in the final parts. The parts produced with higher cooling rate had higher geometric deviations.

Microfluidic biochip injection moulded using a patterned SU-8/Si mould insert

2011 ◽  
Vol 31 (2-3) ◽  
Author(s):  
Akanksha Singh ◽  
Laurent Robert ◽  
Gérard Michel ◽  
Chantal Khan-Malek
Keyword(s):  
Injection Moulding ◽  
Silicon Wafers ◽  
Thermoplastic Polymers ◽  
Mould Insert ◽  
Moulding Process ◽  
Small Series ◽  
Injection Moulding Process ◽  
Silicon Based

Abstract This paper presents the adaptation of a conventional injection moulding process to manufacture microfluidic components in thermoplastic polymers using alternative, exchangeable microstructured silicon-based mould inserts. The mould inserts consist of thick silicon wafers with microfeatures patterned in SU-8 epoxy photo-resist. This process allows changing the mould inserts according to the design, very easily and cost-effectively. The SU-8/Si mould inserts were robust enough to manufacture small series for laboratory purpose. More than a hundred replicas in thin polypropylene (PP) were produced successfully for a biochip designed for protein crystallisation and analysis.

scholarly journals Use of a Holistic Design and Manufacturing Approach to Implement Optimized Additively Manufactured Mould Inserts for the Production of Injection-Moulded Thermoplastics

2020 ◽  
Vol 4 (4) ◽  
pp. 100
Author(s):  
Loucas Papadakis ◽  
Stelios Avraam ◽  
Demetris Photiou ◽  
Simona Masurtschak ◽  
Juan Carlos Pereira Falcón
Keyword(s):  
Cycle Time ◽  
Injection Moulding ◽  
Mould Insert ◽  
Conformal Cooling ◽  
Moulding Process ◽  
Cooling Channels ◽  
Injection Process ◽  
Conformal Cooling Channels ◽  
Injection Moulding Process ◽  
Design And Manufacture

Injection moulding is one the most familiar processes for manufacturing of plastic parts by injecting molten thermoplastic polymers into a metallic mould. The cycle time of this process consists of the phases of injection, packing, cooling, and ejection of the final product. Shortening of cycle time is a key consideration to increase productivity. Therefore, in this manuscript the adoption of additively manufactured mould inserts with conformal cooling channels by means of selective laser melting (SLM) with the aim to reduce process cycles is presented. The design and manufacture of a mould insert with conformal cooling channels for producing pressure fitting thermoplastic parts is described. Numerical analysis of the injection process and simulation of shape distortions after SLM were conducted providing useful results for the design and manufacture of the mould insert. The results of the numerical analyses are compared with experimental 3D geometrical data of the additively manufactured mould insert. Temperature measurements during the real injection moulding process demonstrating promising findings. The adoption of the introduced method for the series production of injection moulded thermoplastics proves a shortening of cycle times of up to 32% and a final product shape quality improvement of up to 77% when using mould inserts with conformal cooling channels over the conventional mould inserts.

scholarly journals Crystallinity control in parts produced from stereolithography injection mould tooling

2003 ◽  
Vol 217 (4) ◽  
pp. 269-276 ◽  
Author(s):  
R A Harris ◽  
R J M Hague ◽  
P M Dickens
Keyword(s):  
Material Property ◽  
Injection Moulding ◽  
Degree Of Crystallinity ◽  
Scanning Calorimetry ◽  
Mould Material ◽  
Moulding Process ◽  
Process Modification ◽  
Injection Moulding Process ◽  
Metal Tooling ◽  
Metal Tools

The use of moulds produced by stereolithography (SL) for injection moulding provides a quick route to manufacturing a low volume of parts without expensivehard tooling. However, these parts have been shown to exhibit different material property characteristics than those produced from metal tooling. The aim of the present work is to research methods that would allow SL moulds to produce parts of similar material property characteristics to those from conventional metal tools. This work has identified that the different part characteristics are due to differing levels of crystallinity developed in the parts from the comparative mould varieties (SL and metal). These crystallinity differences have been associated with the cooling rates imparted owing to the thermal properties of the mould material. The latter part of this work concerns controlling and manipulating this degree of crystallinity. After a discussion of possible methods, two approaches are taken to modifying the crystalline content of parts produced by SL moulds. One of the approaches is material based, the other concerns the injection moulding process. Differential scanning calorimetry (DSC) is used to quantify the resulting levels of crystallinity in the parts. The results show that by process modification it is possible to produce parts by SL moulding that possess a similar crystalline content to those moulded from metal tooling. The use of modified materials allows parts created in SL and metal tools to be of a consistent crystalline content. The work concludes that not only are SL moulds capable of producing parts that are more like those from metal moulds but also present some unique opportunities that have been demonstrated to be unachievable in metal moulds.

Application of RSM to Optimize Moulding Conditions for Minimizing Shrinkage in Thermoplastic Processing

2016 ◽  
Vol 700 ◽  
pp. 12-21 ◽  
Author(s):  
S.M. Nasir ◽  
K.A. Ismail ◽  
Z. Shayfull
Keyword(s):  
Injection Moulding ◽  
Variable Parameter ◽  
Acrylonitrile Butadiene Styrene ◽  
Cooling Time ◽  
Inlet Temperature ◽  
Melt Temperature ◽  
Mould Material ◽  
Moulding Process ◽  
Packing Pressure ◽  
Injection Moulding Process

This study focuses on the analysis of plastic injection moulding process simulation using Autodesk Moldflow Insight (AMI) software in order to minimize shrinkage by optimizing the process parameters. Two types of gates which is single and dual gates have been analysed. Nessei NEX 1000 injection moulding machine and P20 mould material details are incorporated in this study on top of Acrylonitrile Butadiene Styrene (ABS) as a moulded thermoplastic material. Coolant inlet temperature, melt temperature, packing pressure and cooling time are selected as a variable parameter. Design Expert software is obtained as a medium for analysis and optimisation to minimize the shrinkage. The polynomial models are obtained using Design of Experiment (DOE) integrated with RSM Center Composite Design (CCD) method in this study. The results show that packing pressure is a main factor that contributed to shrinkage followed by coolant inlet temperature, while melt temperature and cooling time has less significant for both single and dual gates. Meanwhile, single gate shows a better result of shrinkage compared to the dual gates.

Warpage Analysis of Single and Dual Gates Designed for Injection Moulding Using Response Surface Methodology

2015 ◽  
Vol 754-755 ◽  
pp. 775-783 ◽  
Author(s):  
S.M. Nasir ◽  
Khairul Azwan Ismail ◽  
Z. Shayfull ◽  
M.A. Fairuz
Keyword(s):  
Injection Moulding ◽  
Variable Parameter ◽  
Acrylonitrile Butadiene Styrene ◽  
Inlet Temperature ◽  
Melt Temperature ◽  
Mould Material ◽  
Moulding Process ◽  
Packing Pressure ◽  
Injection Moulding Process ◽  
Mould Design

This study focuses on the analysis of plastic injection moulding process simulation using Autodesk Moldflow Insight (AMI) software in order to correlate between process parameters as an input and warpage as an output for single and dual gates mould design. Nessei NEX 1000 injection moulding machine and P20 mould material details are incorporated in this study on top of Acrylonitrile Butadiene Styrene (ABS) as a moulded thermoplastic material. Coolant inlet temperature, material melt temperature, packing pressure and packing time are selected as a variable parameter. Design Expert software is obtained as a medium for analysis and optimization of input variables in order to minimize the warpage. RSM method as well as Analysis of Variance (ANOVA) has been applied in this study. The results of ANOVA show that some interactions between factors are significant towards warpage existence, which is coolant inlet temperature, material melt temperature and packing pressure. Furthermore, the model created using RSM can be used for warpage prediction and improvement due to a minimum value of error. From this study, the dual gate is the best solution which able to improve the warpage up to 80% instead of single.

scholarly journals Polymer based microneedle patch fabricated using microinjection moulding

2018 ◽  
Vol 192 ◽  
pp. 01039 ◽  
Author(s):  
Pattanaphong Janphuang ◽  
Mongkhol Laebua ◽  
Chanwut Sriphung ◽  
Phatsakon Taweewat ◽  
Anan Sirichalarmkul ◽  
...  
Keyword(s):  
Injection Moulding ◽  
Production Efficiency ◽  
Electrical Discharge Machining ◽  
Low Cost ◽  
Injection Pressure ◽  
Mould Insert ◽  
Moulding Process ◽  
Injection Moulding Process ◽  
Microneedle Patch ◽  
Microinjection Moulding

This paper presents the development of a polymer based microneedle patch for transdermal drug delivery application using plastic microinjection moulding. Design and analysis of the microneedle cavities and mould insert used in the injection moulding process were carried out using Computer-Aided Engineering (CAE) software. A mould insert with low surface roughness was fabricated using Micro Electrical Discharge Machining (μ-EDM). The injection moulding parameters including clamping force, temperature, injection pressure and velocity were characterized in order to obtain the optimum reproducibility. Solid truncated cone microneedles, made of biocompatible polymethyl methacrylate (PMMA), with a round tip radius of 50 μm and 500 μm in height have been realized by microinjection moulding process demonstrating the potential of a low cost, high production efficiency, and suitable for mass production. In addition, a mould insert of cylindrical microneedles fabricated using X-ray LIGA has been proposed.

Evaluation of Cadmould Software to Simulate the Filling Phase of a Natural Rubber Compound in Injection Moulding Process

2013 ◽  
Vol 747 ◽  
pp. 571-574 ◽  
Author(s):  
Zulkifli Mohamad Ariff ◽  
T.H. Khang
Keyword(s):  
Natural Rubber ◽  
Injection Moulding ◽  
Input Data ◽  
Cure Kinetics ◽  
Rubber Compound ◽  
Moulding Process ◽  
Related Data ◽  
Mould Filling ◽  
Injection Moulding Process ◽  
Material Input

The possibility of using Cadmould software to simulate the filling behaviour of a natural rubber compound during an injection moulding process was investigated. For the simulation process, the determination of required material input data involving the rheological and cure kinetics data of the designed rubber compound were conducted. It was discovered that the acquired data were able to function as reliable material input data as they were comparable with related data available in the Cadmould software materials database. Verification of the simulated filling profiles by experimental short shots specimens showed that the Cadmould Rubber Package was able to predict the realistic filling behaviour of the formulated natural rubber compound inside the mould cavity when the measured material data were utilized. Whereas, the usage of available material database from the software failed to model the mould filling progression of the intended natural rubber compound.

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