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1

Mold Temperature and Its Effect on Selected Properties of Cast AlSi5Cu2Mg Alloy

Širanec L., Bolibruchová D., Chalupova M.

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 2

57--62

EN

The European Commission's ambitious plan to reduce CO2 emissions has a significant impact on the global automotive industry. Recent development of new diesel and petrol engines with direct injection is aimed at improving fuel efficiency while maintaining (or enhancing) engine performance. This naturally also increases the demands on the properties of the most stressed engine components (e.g., cylinder heads, engine blocks, pistons), which leads to the development of new materials. Presented work analysed the effect of different mold temperatures (60; 120; 180 °C) on mechanical, physical properties and microstructure of AlSi5Cu2Mg aluminium alloy. This alloy is currently being used for the production of cylinder head castings. The results showed that the changing mold temperature had an effect on mechanical properties (ultimate tensile strength and Young modulus values). SEM with EDX analysis of intermetallic phases revealed there were no size and morphology changes of Cu, Mg and Fe intermetallic phases when the mold temperature changed. No significant effect of different mold temperature on physical properties (thermal and electrical conductivity) and fracture mechanism occurred during experiment. Optimal combination of mechanical and physical properties of AlSi5Cu2Mg alloy was achieved using a permanent mold with temperature ranging from 120 to 180 °C.

2

Microstructure Evolution and Formation Mechanism of Copper-Silver Alloy Fabricated by Induction Heating Directional Solidification at Different Mold Temperatures

Luo Jihui, Li Yangyang, Huang Yanke, Huang Yuehao, Zheng Yuling

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 1

113--117

EN

Cu-2wt%Ag alloy with diameter of 10 mm was fabricated by induction heating directional solidification (IHDS). The effect of different mold temperatures on microstructure of IHDS Cu-2wt%Ag alloy was investigated. The results show that IHDS Cu-2wt%Ag alloy is mainly composed of coarse columnar grains at mold temperature of 1075°C. While the mold temperature is at 1100°C, 1150°C and 1200°C, respectively, the IHDS Cu-2wt%Ag alloy is composed of columnar grains and equiaxed grains and the number of grains increases. Meanwhile, the growth direction of columnar grains in the edge of alloys deviates from the direction of continuous casting to form “V” shape. While the mold temperature is controlled at high temperature, the induced current increases, which leads to the enhancement of eddy current in the mold. Therefore, the dendrites fall off to form new grains under the effect of eddy stirring, resulting in an increasing in the number of grains.

3

Study on Effects of Mold Temperature on the Injection Molded Article

Han J.-H., Kim Y.-C.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1271--1274

EN

This is a study of the effects of temperature of injection mold on the injection molded article. By supplying water of the proper temperature in the cooling line of mold in the cooling process, the mold was the appropriate temperature, and the deformation of the injection molded article was examined according to the mold temperature. In this study, we conducted simulation analysis and experiments, and the results were analyzed. The minimum deformation of the injection molded article model obtained by supplying 50°C water in the cooling line is 0.003 mm, and the maximum deformation was 0.813 mm. Injection molded article models obtained by supplying 20°C water were found to be a minimum of 0.002 mm, with deformation of up to 0.761 mm. When comparing both conditions, the error rate of injection molded article obtained by supplying 20°C water in the mold cooling line was lower by about 0.18%.

4

On-line temperature recording in a multi cooling channel injection molding tool

Postawa P., Stachowiak T., Grzesiczak D.

Polimery

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2015

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T. 60, nr 5

351--355

EN

In this paper the temperature distribution in injection mold was investigated. For this purpose a special experimental mold was designed and made. This mold has eight independent cooling circuits which were connected to a temperature controller using two rotameters. In order to register temperature changes, four thermocouples placed in various points of the mold under the cavity surface and connected to a recorder. It allowed to transmit the data in real time during the injection process and to determine the temperature profile in various areas of injection molding. The infrared thermal images and temperature distribution profiles of the mold cavity and molded parts were also determined.

PL

Zbadano rozkład temperatury w formie wtryskowej oraz zaprojektowano i wykonano eksperymentalną formę wtryskową wyposażoną w osiem niezależnych obiegów chłodzących, podłączonych do termostatu za pośrednictwem dwóch rotametrów. W celu rejestracji zmian temperatury w różnych punktach formy tuż pod powierzchnią gniazda umieszczono cztery termopary połączone z rejestratorem, które umożliwiały przesyłanie danych, w czasie rzeczywistym, podczas trwania procesu i wyznaczenie profilu temperatury w różnych obszarach formy wtryskowej. Sporządzono też termogramy w podczerwieni i profile rozkładu temperatury gniazda formy oraz wypraski.

5

An experimental investigation on water penetration in the process of water assisted injection molding of polypropylene

Ahmadzai A. Z., Vesh A. H. B.

Polimery

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2009

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T. 54, nr 7-8

564-572

EN

The water penetration phenomenon in the process of water assisted injection molding (WAIM) of a semi-crystalline polymer i.e. polypropylene (PP) was investigated. WAIM has been developed for production of hollow plastic elements and for parts having separate internal void spaces or channels. It offers a cost-effective means of producing the large elements having a good surface finish, reduced weight, and relatively short cycle time. In this study three processing parameters were investigated, namely, water injection delay time, holding time and mold temperature. Their effects on water penetration length, part hollow core characteristic (e.g. wall thickness, core diameter) and shrinkage were explored. The mold cavity shaped a branched pipe (two-head) to be cored out via water penetration. The results indicated that an optimum product, namely, having longer water penetration, lower wall thickness difference, more uniform pipe diameter and low shrinkage could be produced at a higher holding time, a higher mold temperature and at an optimum delay time.

PL

Proces wtryskiwania wspomaganego wodą (WAIM) opracowano do produkcji z tworzyw polimerowych elementów mających puste kanały lub puste przestrzenie innego kształtu. Metoda ta pozwala na efektywne ekonomicznie formowanie, w stosunkowo krótko trwającym procesie, dużych elementów charakteryzujących się dobrym wykończeniem powierzchni i względnie mała masą. W ramach tej pracy badano wpływ na penetrację wody w uplastycznionym tworzywie znajdującym się w gnieździe formującym (rys. 1) i związaną z tym charakterystykę wytwarzanych elementów (np. grubość ścianki, średnica kanału, skurcz) trzech parametrów procesowych tj. opóźnienia wtrysku wody (czas upływający od rozpoczęcia wtrysku tworzywa ciekłego do momentu wtrysku wody, ang. delay time), czasu docisku (ang. holding time) oraz temperatury formowania (rys. 5-11, 13, 14). Badania przeprowadzono formując rozgałęzioną (dwuramienną) rurkę, której pusty rdzeń uzyskano dzięki penetracji wtryskiwanej wody (rys. l -4). Stwierdzono, że produkt o najlepszej charakterystyce (tj. odpowiedniej długości penetracji wody w ciekłym polipropylenie, małej różnicy grubości ścianek, jednakowej średnicy kanałów i małym skurczu) uzyskuje się stosując dłuższy czas docisku (10s), wyższą temperaturę formowania (50°) i średni czas opóźnienia wtrysku wody (5s).