The Influence of Segregation Phenomena on Quality of Product in Extrusion Process

• Autorzy: Skorulski G. , Piwnik J. , Baranowski P.
• Języki publikacji: EN

Abstrakty

EN

The segregation phenomena and formation of agglomerate have the basic influence on structure of the final product. The aim of this work is analyzing the phenomena of segregation in semi-solid extrusion process, using several kind of substitute materials, which can simulate the thixotrophic fluid behavior and displacement of solid particles. The experimental researches are made to investigation of segregation in the near-wall layers and the formation of agglomerate. Especially, the distribution of the solid particles at the end of extrusion process have been taken into consideration. Theoretical criteria describe the critical value of the energy liberated at the surfaces by the action of forces depends on the temperature, the pressure, the yield stress and the physical state and degree of intimacy of the contacting surfaces. The theory has been tested experimentally using a silicon polymer as a substitute material. Experimental stand with a Plexiglass die was prepared, such that the velocity fields at the surfaces could be observed and measured during plastic flow, allowing the empirical coefficients in the mathematical formulation to be estimated. On the basis of the theory and experiment an optimal die chamber was designed for a die with a complex shape.

Słowa kluczowe

EN

innovative foundry materials; innovative foundry technologies; thixoforming; experimental modelling; segregation phenomena; semi-liquid aluminium alloys

PL

innowacyjne materiały odlewnicze; innowacyjne technologie odlewnicze; tiksoformowanie; modelowanie eksperymentalne; zjawiska segregacji; półpłynne stopy aluminium

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2010
• Tom: Vol. 10, iss. 3 spec.
• Strony: 251--254
• Opis fizyczny: Bibliogr. 15 poz., il., rys.

Twórcy

autor

Skorulski G.

• Technical University of Białystok, Chair of Mechanical Technology, Wiejska St. 45C , 15-351 Białystok, Poland

autor

Piwnik J.

• Technical University of Białystok, Chair of Mechanical Technology, Wiejska St. 45C , 15-351 Białystok, Poland

autor

Baranowski P.

• COBRABiD sp. z o.o., 00-842 Warszawa, ul. Łucka 15

Bibliografia

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