Crystallinity of parts from multicavity injection mould

• Autorzy: Jaruga T. , Bociąga E.
• Języki publikacji: PL

Abstrakty

EN

Purpose: The intention of this research was to test, if injection moulded polyoxymethylene parts, manufactured in different cavities of the multicavity injection mould with geometrically balanced runners, differ in crystallinity degree. Design/methodology/approach: The values of crystallinity degree were calculated on the basis of DSC (Dynamic Scanning Calorimetry) testing method results (DSC curves). Findings: It was found that there are differences in crystallinity degree for parts from particular mould cavities. The reason of this is the difference in thermal conditions, specific for each cavity. Research limitations/implications: It is supposed that the parts from each multicavity injection mould would have differences in properties. However, it is always dependent on cavities and runners’ layout. Since in this research a particular injection mould was used, the conclusions can not be directly extrapolated to other moulds. Each case requires its own analysis. Higher crystallinity degree will occur in parts obtained from areas of higher mould temperature. Practical implications: The results of this investigation are important for mould designers, especially when moulds are used for precision injection moulding. It was proved here that differences in parts’ properties can occur for multicavity injection moulds. In order to avoid this it is required to minimize the temperature differences in the mould. Originality/value: Geometrically balanced runners in the mould were supposed to assure the equal filling of all cavities. The results obtained lately by other researchers have shown that this is not always true. That investigation was mostly focused on filling imbalance that leads for example to difference in weight of parts from different cavities. In this paper it was shown that not only weight of parts can differ but also other properties.

Słowa kluczowe

PL

obróbka plastyczna; formowanie wtryskowe; stopień krystaliczności

EN

plastic forming; injection moulding; crystallinity degree

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2008
• Tom: Vol. 30, nr 1
• Strony: 53--56
• Opis fizyczny: Bibliogr. 18 poz.

Twórcy

autor

Jaruga T.

autor

Bociąga E.

Bibliografia

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