Rheological characterisation of Al2O3slips for aqueous low pressure injection moulding

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.

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Rheological characterisation of Al2O3 slips for aqueous low pressure injection moulding

CrossRef Listing of Deleted DOIs ◽

10.1179/096797800680794 ◽

2000 ◽

Vol 99 (2) ◽

pp. 92-95 ◽

Cited By ~ 3

Author(s):

A.J. Millán ◽

M. Bravo ◽

R. Moreno ◽

M.I. Nieto

Keyword(s):

Injection Moulding ◽

Low Pressure ◽

Pressure Injection

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Electrochemical Performance of Cone-Shaped Tubular Anode Supported Solid Oxide Fuel Cells Fabricated by Low-Pressure Injection Moulding Technique

ECS Transactions ◽

10.1149/1.3570039 ◽

2019 ◽

Vol 35 (1) ◽

pp. 609-614 ◽

Cited By ~ 2

Author(s):

Jie Xiao ◽

Jiang Liu ◽

Jiao Ding

Keyword(s):

Fuel Cells ◽

Electrochemical Performance ◽

Solid Oxide Fuel Cells ◽

Injection Moulding ◽

Low Pressure ◽

Solid Oxide ◽

Oxide Fuel ◽

Pressure Injection

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The effect of water on the behaviour of alumina–paraffin suspensions for low-pressure injection moulding (LPIM)

Journal of the European Ceramic Society ◽

10.1016/s0955-2219(00)00083-2 ◽

2000 ◽

Vol 20 (12) ◽

pp. 2175-2181 ◽

Cited By ~ 21

Author(s):

S Novak ◽

A Dakskobler ◽

V Ribitsch

Keyword(s):

Injection Moulding ◽

Low Pressure ◽

Effect Of Water ◽

Pressure Injection

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Effect of PEG-based binder concentration on the mechanical properties of lithium disilicate glass-ceramics prepared by low-pressure injection moulding

Processing and Application of Ceramics ◽

10.2298/pac2103238k ◽

2021 ◽

Vol 15 (3) ◽

pp. 238-245

Author(s):

Arnon Kraipok ◽

Pratthana Intawin ◽

Manlika Kamnoy ◽

Suchittra Inthong ◽

Wilaiwan Leenakul ◽

...

Keyword(s):

Mechanical Properties ◽

Injection Moulding ◽

Glass Powder ◽

Acetic Acid Solution ◽

Glass Ceramics ◽

Lithium Disilicate ◽

Sintered Sample ◽

Low Pressure ◽

Bending Test ◽

Pressure Injection

Lithium disilicate (LD) glass-ceramics are extensively employed in restorative dentistry because their superior aesthetic properties and hardness are similar to natural teeth. The aim of this work is to investigate the mechanical properties and chemical solubility of lithium disilicate glass-ceramics prepared by the low-pressure injection moulding using the PEG-based binder. The glass-to-binder ratio was varied as 60:40, 55:45, 50:50 and 45:55 vol.%. The sintering conditions of 800?C with 2 h dwell time were selected according to thermal analysis. Phase formation, microstructure and mechanical properties of the prepared samples were characterized by XRD, SEM, microhardness and three-point bending test, respectively. Besides, the chemical solubility of the system was investigated by the immersion test in acetic acid solution. XRD analyses of the sintered sample confirmed the presence of only one prominent crystalline phase of LD. SEM result showed that the porosity increased with decreasing glass powder content. The mechanical properties of the LD glass-ceramic samples tended to decrease when the proportion of the glass powder decreased, while the chemical solubility tended to increase. The mechanical properties of the glass-ceramics, i.e. the highest density value, Vickers hardness and flexural strength were 2.55 g/cm3, 6.80GPa, and 176MPa, respectively. These results could be useful in developing these LD glass-ceramics for their optimal use in dental applications.

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