Rheological properties of alumina feedstocks for the low-pressure injection moulding process

2009 ◽  
Vol 29 (9) ◽  
pp. 1595-1602 ◽  
Author(s):  
Birgit Loebbecke ◽  
Regina Knitter ◽  
Jürgen Haußelt
Keyword(s):  
Rheological Properties ◽  
Injection Moulding ◽  
Low Pressure ◽  
Moulding Process ◽  
Pressure Injection ◽  
Injection Moulding Process

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.

Rheological properties of paraffin suspensions of surface-modified alumina powder for low-pressure injection moulding

2004 ◽  
Vol 43 (5) ◽  
pp. 559-566 ◽  
Author(s):  
Saša Novak ◽  
Susana Maria Henriques Olhero ◽  
José Maria Fonte Ferreira ◽  
Andreja Zupančič
Keyword(s):  
Rheological Properties ◽  
Injection Moulding ◽  
Low Pressure ◽  
Alumina Powder ◽  
Modified Alumina ◽  
Pressure Injection ◽  
Surface Modified

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.

Multi-Response Parameters Optimisation for Energy-Efficient Injection Moulding Process via Dynamic Shainin DOE Method

2013 ◽  
Vol 554-557 ◽  
pp. 1669-1682 ◽  
Author(s):  
Kam Hoe Yin ◽  
Hui Leng Choo ◽  
Dunant Halim ◽  
Chris Rudd
Keyword(s):  
Energy Consumption ◽  
Process Parameters ◽  
Injection Moulding ◽  
Shop Floor ◽  
Operational Experience ◽  
Moulding Process ◽  
Part Quality ◽  
Control Factors ◽  
Injection Moulding Process ◽  
Signal Response

Process parameters optimisation has been identified as a potential approach to realise a greener injection moulding process. However, reduction in the process energy consumption does not necessarily imply a good part quality. An effective multi-response optimisation process can be demanding and often relies on extensive operational experience from human operators. Therefore, this research focuses on an attempt to develop a more user-friendly approach which could simultaneously deal with the requirements of energy efficiency and part quality. This research proposes a novel approach using a dynamic Shainin Design of Experiment (DOE) methodology to determine an optimal combination of process parameters used in the injection moulding process. The Shainin DOE method is adopted to pinpoint the most important factors on energy consumption and the targeted part quality whereas the ‘dynamic’ term refers to the signal-response system. The effectiveness of the proposed approach was illustrated by investigating the influence of various dominant parameters on the specific energy consumption (SEC) and the Charpy impact strength (CIS) of polypropylene (PP) material after being injection-moulded into impact test specimens. From the experimental results, barrel temperature was identified as the signal factor while mould temperature and cooling time were used as control factors in the full factorial experiments. Then, response function modelling (RFM) was built to characterise the signal-response relationship as a function of the control factors. Finally, RFM led to a trade-off solution where reducing part-to-part variation for CIS resulted in an increase of SEC. Therefore, the research outcomes have demonstrated that the proposed methodology can be practically applied at the factory shop floor to achieve different performance output targets specified by the customer or the manufacturer’s intent.

Modelling for Injection Moulding Process Based on Principal Component Regression Method

2011 ◽  
Author(s):  
Nong Gu. ◽  
Dougas Creighton ◽  
Saeid Nahavandi ◽  
Francisco Chinesta ◽  
Yvan Chastel ◽  
...  
Keyword(s):  
Injection Moulding ◽  
Principal Component Regression ◽  
Principal Component ◽  
Regression Method ◽  
Moulding Process ◽  
Injection Moulding Process

Monitoring of Polymer Plastication in the Injection Moulding Process

2013 ◽  
Author(s):  
Thuy Linh Pham ◽  
Jean Balcaen ◽  
Sambor Chhay ◽  
Yves Bereaux ◽  
Jean-Yves Charmeau
Keyword(s):  
Injection Moulding ◽  
Optical Glass ◽  
Experimental Studies ◽  
Fibre Length ◽  
Rotation Frequency ◽  
Direct Function ◽  
Moulding Process ◽  
Melt Pool ◽  
Injection Moulding Process ◽  
Mechanical Dissipation

In injection moulding or in extrusion, plastication is the step during which polymer pellets are melted by the means of mechanical dissipation provided by a rotating screw and by thermal conduction coming from a heated metallic barrel. This step is crucial for melt thermal homogeneity, charge dispersion and fibre length preservation. Although there have been a large number of theoretical and experimental studies of plastication during the past decades, mostly on extrusion and mostly using the screw extraction technique, extremely few of them have dealt with trying to visualise plastication, let alone measuring the plastication profile in real-time. As a matter of fact, designing such an equipment is an arduous task. We designed an industry-sized metallic barrel, featuring 3 optical glass windows; each window possessing 3 plane faces itself to allow for visualisation and record by synchronised cameras and lightening by lasers. The images recorded can be further analysed by digital image processing. Preliminary results confirm the plastication theory and show a compacted solid bed and a melt pool side by side. The total plastication length is a direct function of screw rotation frequency as it is obvious from results on the melt pool width, which increases when the screw rotation frequency decreases. However, some evidence of solid bed breakage has been recorded, whereby the solid bed does not diminish continuously along the screw but is fractured in the compression zone.

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