Residual stress distribution in injection molded parts

• Autorzy: Postawa P. , Kwiatkowski D.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The paper presents the results of the investigations of influence of the amorphous polystyrene (PS) processing on the diversity of the internal stresses observed in the injection moulded piece. Design/methodology/approach: For the tests, the standardized mould piece designed for the investigations of the processing shrinkage of thermoplastics materials has been used. The samples have been prepared using the Design of Experiment (DoE) theory. The state of internal stresses has been analysed by means of photoelastic method (used stress viewer equipment) on the basis of the layout and size of the isochromatics (fields with the same colour), which determine the mould piece’s areas where the same value for the difference of main tensions. In the article the results of investigations of influence of 5 chosen processing parameters such as injection temperature Tw, mould temperature Tf, clamping pressure pd, cooling time tch and the injection speed vw on the changes in isochromatics layout as a determinant for diversity of internal stresses in injection moulded pieces have been presented. Findings: The performed investigations of the influence of injection conditions on the state of internal stresses reached for injection mould pieces were to determine the parameters of injection at which the achieved state of the stresses in the mould piece (described by the difference of main tensions) will show the lowest values. Practical implications: Effects of examinations of influence of processing conditions on residual stress in injection molded parts (presented in the article) could find practical application in polymer industry, both small and large enterprises. Originality/value: New approach to fast estimation of value of residual stresses were present in the paper.

Słowa kluczowe

EN

engineering polymers; mechanical properties; injection molding; residual stresses

PL

tworzywa konstrukcyjne; właściwości mechaniczne; wtryskiwanie; naprężenia własne

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 18, nr 1-2
• Strony: 171--174
• Opis fizyczny: Bibliogr. 17 poz., rys., tab.

Twórcy

autor

Postawa P.

• Institute of Polymer Processing and Production Management, Czestochowa University of Technology, Al. Armii Krajowej 19c, 42-200 Czestochowa, Poland

autor

Kwiatkowski D.

• Institute of Polymer Processing and Production Management, Czestochowa University of Technology, Al. Armii Krajowej 19c, 42-200 Czestochowa, Poland

Bibliografia

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