Novas
Tecnologias - NTF 5 |
Title
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PRODUCTION OF COMPLEX PARTS BY LOW-PRESSURE INJECTION MOLDING OF GRANITE POWDERS.
Part I - Preparation of feedstock, injection and debinding |
Abstract
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During the quarrying of the ornamental stones in Ceará state (Northeastern
Brazil), a great amount of waste material is produced. Since most of this
powder has not found economic use to date, it is simply, discarded becoming
a potential environmental hazard. This paper describes the use of granite
powder as feedstock for powder injection moulding, thus replacing costly
ceramic materials. Initially the selected powder was milled and sieved. The
resultant fines were then characterised by x-ray diffraction and scanning
electron microscopy and the particle characteristics were also determined.
The characterised material was mixed with a low-viscosity organic vehicle
comprised of carnauba wax, low-density polyethylene and stearic acid.
Rheology studies were performed in order to determine the optimum powder
content compatible with the low-pressure injection moulding process, and the
mixture was injected. Small thread-guides were produced using a two-cavities
mould manufactured from low-carbon steel. Thermal analysis was employed to
determine the appropriate debinding schedule. Investigation of both
as-moulded and debound parts showed that the granite powder has a great
potential as a substitute for more expensive ceramic materials.
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Autores
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Nogueira, Ricardo Emílio F. Q.
Felix, Paulo César G.
Blazdell, Philip Frank
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Trabalho
Completo : |
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1o.
Cobef | Comissão
Organizadora | Palestras |
Sessões Técnicas | Autor | Revisores |
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